Tag Archives: java

Security updates for Monday

Post Syndicated from ris original https://lwn.net/Articles/756489/rss

Security updates have been issued by CentOS (procps, xmlrpc, and xmlrpc3), Debian (batik, prosody, redmine, wireshark, and zookeeper), Fedora (jasper, kernel, poppler, and xmlrpc), Mageia (git and wireshark), Red Hat (rh-java-common-xmlrpc), Slackware (git), SUSE (bzr, dpdk-thunderxdpdk, and ocaml), and Ubuntu (exempi).

Security updates for Thursday

Post Syndicated from ris original https://lwn.net/Articles/756164/rss

Security updates have been issued by CentOS (389-ds-base, corosync, firefox, java-1.7.0-openjdk, java-1.8.0-openjdk, kernel, librelp, libvirt, libvncserver, libvorbis, PackageKit, patch, pcs, and qemu-kvm), Fedora (asterisk, ca-certificates, gifsicle, ncurses, nodejs-base64-url, nodejs-mixin-deep, and wireshark), Mageia (thunderbird), Red Hat (procps), SUSE (curl, kvm, and libvirt), and Ubuntu (apport, haproxy, and tomcat7, tomcat8).

Security updates for Monday

Post Syndicated from ris original https://lwn.net/Articles/755796/rss

Security updates have been issued by Debian (batik, cups, gitlab, ming, and xdg-utils), Fedora (dpdk, firefox, glibc, nodejs-deep-extend, strongswan, thunderbird, thunderbird-enigmail, wavpack, xdg-utils, and xen), Gentoo (ntp, rkhunter, and zsh), openSUSE (Chromium, GraphicsMagick, jasper, opencv, pdns, and wireshark), SUSE (jasper, java-1_7_1-ibm, krb5, libmodplug, and openstack-nova), and Ubuntu (thunderbird).

Security updates for Friday

Post Syndicated from ris original https://lwn.net/Articles/755667/rss

Security updates have been issued by Arch Linux (bind, libofx, and thunderbird), Debian (thunderbird, xdg-utils, and xen), Fedora (procps-ng), Mageia (gnupg2, mbedtls, pdns, and pdns-recursor), openSUSE (bash, GraphicsMagick, icu, and kernel), Oracle (thunderbird), Red Hat (java-1.7.1-ibm, java-1.8.0-ibm, and thunderbird), Scientific Linux (thunderbird), and Ubuntu (curl).

C is to low level

Post Syndicated from Robert Graham original https://blog.erratasec.com/2018/05/c-is-too-low-level.html

I’m in danger of contradicting myself, after previously pointing out that x86 machine code is a high-level language, but this article claiming C is a not a low level language is bunk. C certainly has some problems, but it’s still the closest language to assembly. This is obvious by the fact it’s still the fastest compiled language. What we see is a typical academic out of touch with the real world.

The author makes the (wrong) observation that we’ve been stuck emulating the PDP-11 for the past 40 years. C was written for the PDP-11, and since then CPUs have been designed to make C run faster. The author imagines a different world, such as where CPU designers instead target something like LISP as their preferred language, or Erlang. This misunderstands the state of the market. CPUs do indeed supports lots of different abstractions, and C has evolved to accommodate this.

The author criticizes things like “out-of-order” execution which has lead to the Spectre sidechannel vulnerabilities. Out-of-order execution is necessary to make C run faster. The author claims instead that those resources should be spent on having more slower CPUs, with more threads. This sacrifices single-threaded performance in exchange for a lot more threads executing in parallel. The author cites Sparc Tx CPUs as his ideal processor.

But here’s the thing, the Sparc Tx was a failure. To be fair, it’s mostly a failure because most of the time, people wanted to run old C code instead of new Erlang code. But it was still a failure at running Erlang.

Time after time, engineers keep finding that “out-of-order”, single-threaded performance is still the winner. A good example is ARM processors for both mobile phones and servers. All the theory points to in-order CPUs as being better, but all the products are out-of-order, because this theory is wrong. The custom ARM cores from Apple and Qualcomm used in most high-end phones are so deeply out-of-order they give Intel CPUs competition. The same is true on the server front with the latest Qualcomm Centriq and Cavium ThunderX2 processors, deeply out of order supporting more than 100 instructions in flight.

The Cavium is especially telling. Its ThunderX CPU had 48 simple cores which was replaced with the ThunderX2 having 32 complex, deeply out-of-order cores. The performance increase was massive, even on multithread-friendly workloads. Every competitor to Intel’s dominance in the server space has learned the lesson from Sparc Tx: many wimpy cores is a failure, you need fewer beefy cores. Yes, they don’t need to be as beefy as Intel’s processors, but they need to be close.

Even Intel’s “Xeon Phi” custom chip learned this lesson. This is their GPU-like chip, running 60 cores with 512-bit wide “vector” (sic) instructions, designed for supercomputer applications. Its first version was purely in-order. Its current version is slightly out-of-order. It supports four threads and focuses on basic number crunching, so in-order cores seems to be the right approach, but Intel found in this case that out-of-order processing still provided a benefit. Practice is different than theory.

As an academic, the author of the above article focuses on abstractions. The criticism of C is that it has the wrong abstractions which are hard to optimize, and that if we instead expressed things in the right abstractions, it would be easier to optimize.

This is an intellectually compelling argument, but so far bunk.

The reason is that while the theoretical base language has issues, everyone programs using extensions to the language, like “intrinsics” (C ‘functions’ that map to assembly instructions). Programmers write libraries using these intrinsics, which then the rest of the normal programmers use. In other words, if your criticism is that C is not itself low level enough, it still provides the best access to low level capabilities.

Given that C can access new functionality in CPUs, CPU designers add new paradigms, from SIMD to transaction processing. In other words, while in the 1980s CPUs were designed to optimize C (stacks, scaled pointers), these days CPUs are designed to optimize tasks regardless of language.

The author of that article criticizes the memory/cache hierarchy, claiming it has problems. Yes, it has problems, but only compared to how well it normally works. The author praises the many simple cores/threads idea as hiding memory latency with little caching, but misses the point that caches also dramatically increase memory bandwidth. Intel processors are optimized to read a whopping 256 bits every clock cycle from L1 cache. Main memory bandwidth is orders of magnitude slower.

The author goes onto criticize cache coherency as a problem. C uses it, but other languages like Erlang don’t need it. But that’s largely due to the problems each languages solves. Erlang solves the problem where a large number of threads work on largely independent tasks, needing to send only small messages to each other across threads. The problems C solves is when you need many threads working on a huge, common set of data.

For example, consider the “intrusion prevention system”. Any thread can process any incoming packet that corresponds to any region of memory. There’s no practical way of solving this problem without a huge coherent cache. It doesn’t matter which language or abstractions you use, it’s the fundamental constraint of the problem being solved. RDMA is an important concept that’s moved from supercomputer applications to the data center, such as with memcached. Again, we have the problem of huge quantities (terabytes worth) shared among threads rather than small quantities (kilobytes).

The fundamental issue the author of the the paper is ignoring is decreasing marginal returns. Moore’s Law has gifted us more transistors than we can usefully use. We can’t apply those additional registers to just one thing, because the useful returns we get diminish.

For example, Intel CPUs have two hardware threads per core. That’s because there are good returns by adding a single additional thread. However, the usefulness of adding a third or fourth thread decreases. That’s why many CPUs have only two threads, or sometimes four threads, but no CPU has 16 threads per core.

You can apply the same discussion to any aspect of the CPU, from register count, to SIMD width, to cache size, to out-of-order depth, and so on. Rather than focusing on one of these things and increasing it to the extreme, CPU designers make each a bit larger every process tick that adds more transistors to the chip.

The same applies to cores. It’s why the “more simpler cores” strategy fails, because more cores have their own decreasing marginal returns. Instead of adding cores tied to limited memory bandwidth, it’s better to add more cache. Such cache already increases the size of the cores, so at some point it’s more effective to add a few out-of-order features to each core rather than more cores. And so on.

The question isn’t whether we can change this paradigm and radically redesign CPUs to match some academic’s view of the perfect abstraction. Instead, the goal is to find new uses for those additional transistors. For example, “message passing” is a useful abstraction in languages like Go and Erlang that’s often more useful than sharing memory. It’s implemented with shared memory and atomic instructions, but I can’t help but think it couldn’t better be done with direct hardware support.

Of course, as soon as they do that, it’ll become an intrinsic in C, then added to languages like Go and Erlang.


Academics live in an ideal world of abstractions, the rest of us live in practical reality. The reality is that vast majority of programmers work with the C family of languages (JavaScript, Go, etc.), whereas academics love the epiphanies they learned using other languages, especially function languages. CPUs are only superficially designed to run C and “PDP-11 compatibility”. Instead, they keep adding features to support other abstractions, abstractions available to C. They are driven by decreasing marginal returns — they would love to add new abstractions to the hardware because it’s a cheap way to make use of additional transitions. Academics are wrong believing that the entire system needs to be redesigned from scratch. Instead, they just need to come up with new abstractions CPU designers can add.

Security updates for Wednesday

Post Syndicated from ris original https://lwn.net/Articles/755386/rss

Security updates have been issued by CentOS (java-1.7.0-openjdk, java-1.8.0-openjdk, kernel, libvirt, and qemu-kvm), Debian (procps), Fedora (curl, mariadb, and procps-ng), Gentoo (samba, shadow, and virtualbox), openSUSE (opencv, openjpeg2, pdns, qemu, and wget), Oracle (java-1.8.0-openjdk and kernel), Red Hat (java-1.7.0-openjdk, java-1.8.0-openjdk, kernel, kernel-rt, libvirt, qemu-kvm, qemu-kvm-rhev, redhat-virtualization-host, and vdsm), Scientific Linux (java-1.7.0-openjdk, java-1.8.0-openjdk, kernel, libvirt, and qemu-kvm), Slackware (kernel, mozilla, and procps), SUSE (ghostscript-library, kernel, mariadb, python, qemu, and wget), and Ubuntu (linux-raspi2 and linux-raspi2, linux-snapdragon).

Acunetix v12 – More Comprehensive More Accurate & 2x Faster

Post Syndicated from Darknet original https://www.darknet.org.uk/2018/05/acunetix-v12-more-comprehensive-more-accurate-2x-faster/?utm_source=rss&utm_medium=social&utm_campaign=darknetfeed

Acunetix v12 – More Comprehensive More Accurate & 2x Faster

Acunetix, the pioneer in automated web application security software, has announced the release of Acunetix v12. This new version provides support for JavaScript ES7 to better analyse sites which rely heavily on JavaScript such as SPAs. This coupled with a new AcuSensor for Java web applications, sets Acunetix ahead of the curve in its ability to comprehensively and accurately scan all types of websites.

With v12 also comes a brand new scanning engine, re-engineered and re-written from the ground up, making Acunetix the fastest scanning engine in the industry.

Read the rest of Acunetix v12 – More Comprehensive More Accurate & 2x Faster now! Only available at Darknet.

Security updates for Tuesday

Post Syndicated from ris original https://lwn.net/Articles/755205/rss

Security updates have been issued by Debian (gitlab and packagekit), Fedora (glibc, postgresql, and webkitgtk4), Oracle (java-1.7.0-openjdk, java-1.8.0-openjdk, kernel, libvirt, and qemu-kvm), Red Hat (java-1.7.0-openjdk, kernel-rt, qemu-kvm, and qemu-kvm-rhev), SUSE (openjpeg2, qemu, and squid3), and Ubuntu (kernel, linux, linux-aws, linux-azure, linux-gcp, linux-kvm, linux-oem, linux, linux-aws, linux-kvm,, linux-hwe, linux-azure, linux-gcp, linux-oem, linux-lts-trusty, linux-lts-xenial, linux-aws, qemu, and xdg-utils).

From Framework to Function: Deploying AWS Lambda Functions for Java 8 using Apache Maven Archetype

Post Syndicated from Ryosuke Iwanaga original https://aws.amazon.com/blogs/compute/from-framework-to-function-deploying-aws-lambda-functions-for-java-8-using-apache-maven-archetype/

As a serverless computing platform that supports Java 8 runtime, AWS Lambda makes it easy to run any type of Java function simply by uploading a JAR file. To help define not only a Lambda serverless application but also Amazon API Gateway, Amazon DynamoDB, and other related services, the AWS Serverless Application Model (SAM) allows developers to use a simple AWS CloudFormation template.

AWS provides the AWS Toolkit for Eclipse that supports both Lambda and SAM. AWS also gives customers an easy way to create Lambda functions and SAM applications in Java using the AWS Command Line Interface (AWS CLI). After you build a JAR file, all you have to do is type the following commands:

aws cloudformation package 
aws cloudformation deploy

To consolidate these steps, customers can use Archetype by Apache Maven. Archetype uses a predefined package template that makes getting started to develop a function exceptionally simple.

In this post, I introduce a Maven archetype that allows you to create a skeleton of AWS SAM for a Java function. Using this archetype, you can generate a sample Java code example and an accompanying SAM template to deploy it on AWS Lambda by a single Maven action.


Make sure that the following software is installed on your workstation:

  • Java
  • Maven
  • (Optional) AWS SAM CLI

Install Archetype

After you’ve set up those packages, install Archetype with the following commands:

git clone https://github.com/awslabs/aws-serverless-java-archetype
cd aws-serverless-java-archetype
mvn install

These are one-time operations, so you don’t run them for every new package. If you’d like, you can add Archetype to your company’s Maven repository so that other developers can use it later.

With those packages installed, you’re ready to develop your new Lambda Function.

Start a project

Now that you have the archetype, customize it and run the code:

cd /path/to/project_home
mvn archetype:generate \
  -DarchetypeGroupId=com.amazonaws.serverless.archetypes \
  -DarchetypeArtifactId=aws-serverless-java-archetype \
  -DarchetypeVersion=1.0.0 \
  -DarchetypeRepository=local \ # Forcing to use local maven repository
  -DinteractiveMode=false \ # For batch mode
  # You can also specify properties below interactively if you omit the line for batch mode
  -DgroupId=YOUR_GROUP_ID \
  -DartifactId=YOUR_ARTIFACT_ID \
  -Dversion=YOUR_VERSION \

You should have a directory called YOUR_ARTIFACT_ID that contains the files and folders shown below:

├── event.json
├── pom.xml
├── src
│   └── main
│       ├── java
│       │   └── Package
│       │       └── Example.java
│       └── resources
│           └── log4j2.xml
└── template.yaml

The sample code is a working example. If you install SAM CLI, you can invoke it just by the command below:

mvn -P invoke verify
[INFO] Scanning for projects...
[INFO] ---------------------------< com.riywo:foo >----------------------------
[INFO] Building foo 1.0
[INFO] --------------------------------[ jar ]---------------------------------
[INFO] --- maven-jar-plugin:3.0.2:jar (default-jar) @ foo ---
[INFO] Building jar: /private/tmp/foo/target/foo-1.0.jar
[INFO] --- maven-shade-plugin:3.1.0:shade (shade) @ foo ---
[INFO] Including com.amazonaws:aws-lambda-java-core:jar:1.2.0 in the shaded jar.
[INFO] Replacing /private/tmp/foo/target/lambda.jar with /private/tmp/foo/target/foo-1.0-shaded.jar
[INFO] --- exec-maven-plugin:1.6.0:exec (sam-local-invoke) @ foo ---
2018/04/06 16:34:35 Successfully parsed template.yaml
2018/04/06 16:34:35 Connected to Docker 1.37
2018/04/06 16:34:35 Fetching lambci/lambda:java8 image for java8 runtime...
java8: Pulling from lambci/lambda
Digest: sha256:14df0a5914d000e15753d739612a506ddb8fa89eaa28dcceff5497d9df2cf7aa
Status: Image is up to date for lambci/lambda:java8
2018/04/06 16:34:37 Invoking Package.Example::handleRequest (java8)
2018/04/06 16:34:37 Decompressing /tmp/foo/target/lambda.jar
2018/04/06 16:34:37 Mounting /private/var/folders/x5/ldp7c38545v9x5dg_zmkr5kxmpdprx/T/aws-sam-local-1523000077594231063 as /var/task:ro inside runtime container
START RequestId: a6ae19fe-b1b0-41e2-80bc-68a40d094d74 Version: $LATEST
Log output: Greeting is 'Hello Tim Wagner.'
END RequestId: a6ae19fe-b1b0-41e2-80bc-68a40d094d74
REPORT RequestId: a6ae19fe-b1b0-41e2-80bc-68a40d094d74	Duration: 96.60 ms	Billed Duration: 100 ms	Memory Size: 128 MB	Max Memory Used: 7 MB

{"greetings":"Hello Tim Wagner."}

[INFO] ------------------------------------------------------------------------
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 10.452 s
[INFO] Finished at: 2018-04-06T16:34:40+09:00
[INFO] ------------------------------------------------------------------------

This maven goal invokes sam local invoke -e event.json, so you can see the sample output to greet Tim Wagner.

To deploy this application to AWS, you need an Amazon S3 bucket to upload your package. You can use the following command to create a bucket if you want:

aws s3 mb s3://YOUR_BUCKET --region YOUR_REGION

Now, you can deploy your application by just one command!

mvn deploy \
    -DawsRegion=YOUR_REGION \
    -Ds3Bucket=YOUR_BUCKET \
[INFO] Scanning for projects...
[INFO] ---------------------------< com.riywo:foo >----------------------------
[INFO] Building foo 1.0
[INFO] --------------------------------[ jar ]---------------------------------
[INFO] --- exec-maven-plugin:1.6.0:exec (sam-package) @ foo ---
Uploading to aws-serverless-java/com.riywo:foo:1.0/924732f1f8e4705c87e26ef77b080b47  11657 / 11657.0  (100.00%)
Successfully packaged artifacts and wrote output template to file target/sam.yaml.
Execute the following command to deploy the packaged template
aws cloudformation deploy --template-file /private/tmp/foo/target/sam.yaml --stack-name <YOUR STACK NAME>
[INFO] --- maven-deploy-plugin:2.8.2:deploy (default-deploy) @ foo ---
[INFO] Skipping artifact deployment
[INFO] --- exec-maven-plugin:1.6.0:exec (sam-deploy) @ foo ---

Waiting for changeset to be created..
Waiting for stack create/update to complete
Successfully created/updated stack - archetype
[INFO] ------------------------------------------------------------------------
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 37.176 s
[INFO] Finished at: 2018-04-06T16:41:02+09:00
[INFO] ------------------------------------------------------------------------

Maven automatically creates a shaded JAR file, uploads it to your S3 bucket, replaces template.yaml, and creates and updates the CloudFormation stack.

To customize the process, modify the pom.xml file. For example, to avoid typing values for awsRegion, s3Bucket or stackName, write them inside pom.xml and check in your VCS. Afterward, you and the rest of your team can deploy the function by typing just the following command:

mvn deploy


Lambda Java 8 runtime has some types of handlers: POJO, Simple type and Stream. The default option of this archetype is POJO style, which requires to create request and response classes, but they are baked by the archetype by default. If you want to use other type of handlers, you can use handlerType property like below:

## POJO type (default)
mvn archetype:generate \

## Simple type - String
mvn archetype:generate \

### Stream type
mvn archetype:generate \

See documentation for more details about handlers.

Also, Lambda Java 8 runtime supports two types of Logging class: Log4j 2 and LambdaLogger. This archetype creates LambdaLogger implementation by default, but you can use Log4j 2 if you want:

## LambdaLogger (default)
mvn archetype:generate \

## Log4j 2
mvn archetype:generate \

If you use LambdaLogger, you can delete ./src/main/resources/log4j2.xml. See documentation for more details.


So, what’s next? Develop your Lambda function locally and type the following command: mvn deploy !

With this Archetype code example, available on GitHub repo, you should be able to deploy Lambda functions for Java 8 in a snap. If you have any questions or comments, please submit them below or leave them on GitHub.

Pascutto: Linux sandboxing improvements in Firefox 60

Post Syndicated from corbet original https://lwn.net/Articles/754270/rss

Gian-Carlo Pascutto posts
about the sandboxing improvements
in the Firefox 60 release.
The most important change is that content processes — which render
Web pages and execute JavaScript — are no longer allowed to directly
connect to the Internet, or connect to most local services accessed with
Unix-domain sockets (for example, PulseAudio).

What’s new in HiveMQ 3.4

Post Syndicated from The HiveMQ Team original https://www.hivemq.com/whats-new-in-hivemq-3-4

We are pleased to announce the release of HiveMQ 3.4. This version of HiveMQ is the most resilient and advanced version of HiveMQ ever. The main focus in this release was directed towards addressing the needs for the most ambitious MQTT deployments in the world for maximum performance and resilience for millions of concurrent MQTT clients. Of course, deployments of all sizes can profit from the improvements in the latest and greatest HiveMQ.

This version is a drop-in replacement for HiveMQ 3.3 and of course supports rolling upgrades with zero-downtime.

HiveMQ 3.4 brings many features that your users, administrators and plugin developers are going to love. These are the highlights:


New HiveMQ 3.4 features at a glance


HiveMQ 3.4 brings various improvements in terms of scalability, availability, resilience and observability for the cluster mechanism. Many of the new features remain under the hood, but several additions stand out:

Cluster Overload Protection

The new version has a first-of-its-kind Cluster Overload Protection. The whole cluster is able to spot MQTT clients that cause overload on nodes or the cluster as a whole and protects itself from the overload. This mechanism also protects the deployment from cascading failures due to slow or failing underlying hardware (as sometimes seen on cloud providers). This feature is enabled by default and you can learn more about the mechanism in our documentation.

Dynamic Replicates

HiveMQ’s sophisticated cluster mechanism is able to scale in a linear fashion due to extremely efficient and true data distribution mechanics based on a configured replication factor. The most important aspect of every cluster is availability, which is achieved by having eventual consistency functions in place for edge cases. The 3.4 version adds dynamic replicates to the cluster so even the most challenging edge cases involving network splits don’t lead to the sacrifice of consistency for the most important MQTT operations.

Node Stress Level Metrics

All MQTT cluster nodes are now aware of their own stress level and the stress levels of other cluster members. While all stress mitigation is handled internally by HiveMQ, experienced operators may want to monitor the individual node’s stress level (e.g with Grafana) in order to start investigating what caused the increase of load.


Operators worldwide love the HiveMQ WebUI introduced with HiveMQ 3.3. We gathered all the fantastic feedback from our users and polished the WebUI, so it’s even more useful for day-to-day broker operations and remote debugging of MQTT clients. The most important changes and additions are:

Trace Recording Download

The unique Trace Recordings functionality is without doubt a lifesaver when the behavior of individual MQTT clients needs further investigation as all interactions with the broker can be traced — at runtime and at scale! Huge production deployments may accumulate multiple gigabytes of trace recordings. HiveMQ now offers a convenient way to collect all trace recordings from all nodes, zips them and allows the download via a simple button on the WebUI. Remote debugging was never easier!

Additional Client Detail Information in WebUI

The mission of the HiveMQ WebUI is to provide easy insights to the whole production MQTT cluster for operators and administrators. Individual MQTT client investigations are a piece of cake, as all available information about clients can be viewed in detail. We further added the ability to view the restrictions a concrete client has:

  • Maximum Inflight Queue Size
  • Client Offline Queue Messages Size
  • Client Offline Message Drop Strategy

Session Invalidation

MQTT persistent sessions are one of the outstanding features of the MQTT protocol specification. Sessions which do not expire but are never reused unnecessarily consume disk space and memory. Administrators can now invalidate individual session directly in the HiveMQ WebUI for client sessions, which can be deleted safely. HiveMQ 3.4 will take care and release the resources on all cluster nodes after a session was invalidated

Web UI Polishing

Most texts on the WebUI were revisited and are now clearer and crisper. The help texts also received a major overhaul and should now be more, well, helpful. In addition, many small improvements were added, which are most of the time invisible but are here to help when you need them most. For example, the WebUI now displays a warning if cluster nodes with old versions are in the cluster (which may happen if a rolling upgrade was not finished properly)

Plugin System

One of the most popular features of HiveMQ is the extensive Plugin System, which virtually enables the integration of HiveMQ to any system and allows hooking into all aspects of the MQTT lifecycle. We listened to the feedback and are pleased to announce many improvements, big and small, for the Plugin System:

Client Session Time-to-live for individual clients

HiveMQ 3.3 offered a global configuration for setting the Time-To-Live for MQTT sessions. With the advent of HiveMQ 3.4, users can now programmatically set Time-To-Live values for individual MQTT clients and can discard a MQTT session immediately.

Individual Inflight Queues

While the Inflight Queue configuration is typically sufficient in the HiveMQ default configuration, there are some use cases that require the adjustment of this configuration. It’s now possible to change the Inflight Queue size for individual clients via the Plugin System.

Plugin Service Overload Protection

The HiveMQ Plugin System is a power-user tool and it’s possible to do unbelievably useful modifications as well as putting major stress on the system as a whole if the programmer is not careful. In order to protect the HiveMQ instances from accidental overload, a Plugin Service Overload Protection can be configured. This rate limits the Plugin Service usage and gives feedback to the application programmer in case the rate limit is exceeded. This feature is disabled by default but we strongly recommend updating your plugins to profit from this feature.

Session Attribute Store putIfNewer

This is one of the small bits you almost never need but when you do, you’re ecstatic for being able to use it. The Session Attribute Store now offers methods to put values, if the values you want to put are newer or fresher than the values already written. This is extremely useful, if multiple cluster nodes want to write to the Session Attribute Store simultaneously, as this guarantees that outdated values can no longer overwrite newer values.

Disconnection Timestamp for OnDisconnectCallback

As the OnDisconnectCallback is executed asynchronously, the client might already be gone when the callback is executed. It’s now easy to obtain the exact timestamp when a MQTT client disconnected, even if the callback is executed later on. This feature might be very interesting for many plugin developers in conjunction with the Session Attribute Store putIfNewer functionality.


We ❤️ Operators and we strive to provide all the tools needed for operating and administrating a MQTT broker cluster at scale in any environment. A key strategy for successful operations of any system is monitoring. We added some interesting new metrics you might find useful.

System Metrics

In addition to JVM Metrics, HiveMQ now also gathers Operating System Metrics for Linux Systems. So HiveMQ is able to see for itself how the operating system views the process, including native memory, the real CPU usage, and open file usage. These metrics are particularly useful, if you don’t have a monitoring agent for Linux systems setup. All metrics can be found here.

Client Disconnection Metrics

The reality of many MQTT scenarios is that not all clients are able to disconnect gracefully by sending MQTT DISCONNECT messages. HiveMQ now also exposes metrics about clients that disconnected by closing the TCP connection instead of sending a DISCONNECT packet first. This is especially useful for monitoring, if you regularly deal with clients that don’t have a stable connection to the MQTT brokers.


JMX enabled by default

JMX, the Java Monitoring Extension, is now enabled by default. Many HiveMQ operators use Application Performance Monitoring tools, which are able to hook into the metrics via JMX or use plain JMX for on-the-fly debugging. While we recommend to use official off-the-shelf plugins for monitoring, it’s now easier than ever to just use JMX if other solutions are not available to you.

Other notable improvements

The 3.4 release of HiveMQ is full of hidden gems and improvements. While it would be too much to highlight all small improvements, these notable changes stand out and contribute to the best HiveMQ release ever.

Topic Level Distribution Configuration

Our recommendation for all huge deployments with millions of devices is: Start with separate topic prefixes by bringing the dynamic topic parts directly to the beginning. The reality is that many customers have topics that are constructed like the following: “devices/{deviceId}/status”. So what happens is that all topics in this example start with a common prefix, “devices”, which is the first topic level. Unfortunately the first topic level doesn’t include a dynamic topic part. In order to guarantee the best scalability of the cluster and the best performance of the topic tree, customers can now configure how many topic levels are used for distribution. In the example outlined here, a topic level distribution of 2 would be perfect and guarantees the best scalability.

Mass disconnect performance improvements

Mass disconnections of MQTT clients can happen. This might be the case when e.g. a load balancer in front of the MQTT broker cluster drops the connections or if a mobile carrier experiences connectivity problems. Prior to HiveMQ 3.4, mass disconnect events caused stress on the cluster. Mass disconnect events are now massively optimized and even tens of millions of connection losses at the same time won’t bring the cluster into stress situations.


Replication Performance Improvements

Due to the distributed nature of a HiveMQ, data needs to be replicated across the cluster in certain events, e.g. when cluster topology changes occur. There are various internal improvements in HiveMQ version 3.4, which increase the replication performance significantly. Our engineers put special love into the replication of Queued Messages, which is now faster than ever, even for multiple millions of Queued Messages that need to be transferred across the cluster.

Updated Native SSL Libraries

The Native SSL Integration of HiveMQ was updated to the newest BoringSSL version. This results in better performance and increased security. In case you’re using SSL and you are not yet using the native SSL integration, we strongly recommend to give it a try, more than 40% performance improvement can be observed for most deployments.


Improvements for Java 9

While Java 9 was already supported for older HiveMQ versions, HiveMQ 3.4 has full-blown Java 9 support. The minimum Java version still remains Java 7, although we strongly recommend to use Java 8 or newer for the best performance of HiveMQ.

Security updates for Monday

Post Syndicated from ris original https://lwn.net/Articles/753687/rss

Security updates have been issued by Debian (libdatetime-timezone-perl, libmad, lucene-solr, tzdata, and wordpress), Fedora (drupal7, scummvm, scummvm-tools, and zsh), Mageia (boost, ghostscript, gsoap, java-1.8.0-openjdk, links, and php), openSUSE (pam_kwallet), and Slackware (python).

XXEinjector – Automatic XXE Injection Tool For Exploitation

Post Syndicated from Darknet original https://www.darknet.org.uk/2018/05/xxeinjector-automatic-xxe-injection-tool-for-exploitation/?utm_source=rss&utm_medium=social&utm_campaign=darknetfeed

XXEinjector – Automatic XXE Injection Tool For Exploitation

XXEinjector is a Ruby-based XXE Injection Tool that automates retrieving files using direct and out of band methods. Directory listing only works in Java applications and the brute forcing method needs to be used for other applications.

Usage of XXEinjector XXE Injection Tool

XXEinjector actually has a LOT of options, so do have a look through to see how you can best leverage this type of attack. Obviously Ruby is a prequisite to run the tool.

Read the rest of XXEinjector – Automatic XXE Injection Tool For Exploitation now! Only available at Darknet.

Announcing Local Build Support for AWS CodeBuild

Post Syndicated from Karthik Thirugnanasambandam original https://aws.amazon.com/blogs/devops/announcing-local-build-support-for-aws-codebuild/

Today, we’re excited to announce local build support in AWS CodeBuild.

AWS CodeBuild is a fully managed build service. There are no servers to provision and scale, or software to install, configure, and operate. You just specify the location of your source code, choose your build settings, and CodeBuild runs build scripts for compiling, testing, and packaging your code.

In this blog post, I’ll show you how to set up CodeBuild locally to build and test a sample Java application.

By building an application on a local machine you can:

  • Test the integrity and contents of a buildspec file locally.
  • Test and build an application locally before committing.
  • Identify and fix errors quickly from your local development environment.


In this post, I am using AWS Cloud9 IDE as my development environment.

If you would like to use AWS Cloud9 as your IDE, follow the express setup steps in the AWS Cloud9 User Guide.

The AWS Cloud9 IDE comes with Docker and Git already installed. If you are going to use your laptop or desktop machine as your development environment, install Docker and Git before you start.

Steps to build CodeBuild image locally

Run git clone https://github.com/aws/aws-codebuild-docker-images.git to download this repository to your local machine.

$ git clone https://github.com/aws/aws-codebuild-docker-images.git

Lets build a local CodeBuild image for JDK 8 environment. The Dockerfile for JDK 8 is present in /aws-codebuild-docker-images/ubuntu/java/openjdk-8.

Edit the Dockerfile to remove the last line ENTRYPOINT [“dockerd-entrypoint.sh”] and save the file.

Run cd ubuntu/java/openjdk-8 to change the directory in your local workspace.

Run docker build -t aws/codebuild/java:openjdk-8 . to build the Docker image locally. This command will take few minutes to complete.

$ cd aws-codebuild-docker-images
$ cd ubuntu/java/openjdk-8
$ docker build -t aws/codebuild/java:openjdk-8 .

Steps to setup CodeBuild local agent

Run the following Docker pull command to download the local CodeBuild agent.

$ docker pull amazon/aws-codebuild-local:latest --disable-content-trust=false

Now you have the local agent image on your machine and can run a local build.

Run the following git command to download a sample Java project.

$ git clone https://github.com/karthiksambandam/sample-web-app.git

Steps to use the local agent to build a sample project

Let’s build the sample Java project using the local agent.

Execute the following Docker command to run the local agent and build the sample web app repository you cloned earlier.

$ docker run -it -v /var/run/docker.sock:/var/run/docker.sock -e "IMAGE_NAME=aws/codebuild/java:openjdk-8" -e "ARTIFACTS=/home/ec2-user/environment/artifacts" -e "SOURCE=/home/ec2-user/environment/sample-web-app" amazon/aws-codebuild-local

Note: We need to provide three environment variables namely  IMAGE_NAME, SOURCE and ARTIFACTS.

IMAGE_NAME: The name of your build environment image.

SOURCE: The absolute path to your source code directory.

ARTIFACTS: The absolute path to your artifact output folder.

When you run the sample project, you get a runtime error that says the YAML file does not exist. This is because a buildspec.yml file is not included in the sample web project. AWS CodeBuild requires a buildspec.yml to run a build. For more information about buildspec.yml, see Build Spec Example in the AWS CodeBuild User Guide.

Let’s add a buildspec.yml file with the following content to the sample-web-app folder and then rebuild the project.

version: 0.2

      - echo Build started on `date`
      - mvn install

    - target/javawebdemo.war

$ docker run -it -v /var/run/docker.sock:/var/run/docker.sock -e "IMAGE_NAME=aws/codebuild/java:openjdk-8" -e "ARTIFACTS=/home/ec2-user/environment/artifacts" -e "SOURCE=/home/ec2-user/environment/sample-web-app" amazon/aws-codebuild-local

This time your build should be successful. Upon successful execution, look in the /artifacts folder for the final built artifacts.zip file to validate.


In this blog post, I showed you how to quickly set up the CodeBuild local agent to build projects right from your local desktop machine or laptop. As you see, local builds can improve developer productivity by helping you identify and fix errors quickly.

I hope you found this post useful. Feel free to leave your feedback or suggestions in the comments.

Security updates for Thursday

Post Syndicated from jake original https://lwn.net/Articles/753457/rss

Security updates have been issued by CentOS (firefox, java-1.7.0-openjdk, java-1.8.0-openjdk, librelp, patch, and python-paramiko), Debian (kernel and quassel), Gentoo (chromium, hesiod, and python), openSUSE (corosync, dovecot22, libraw, patch, and squid), Oracle (java-1.7.0-openjdk), Red Hat (go-toolset-7 and go-toolset-7-golang, java-1.7.0-openjdk, and rh-php70-php), and SUSE (corosync and patch).

Security updates for Tuesday

Post Syndicated from ris original https://lwn.net/Articles/753257/rss

Security updates have been issued by Fedora (cups-filters, ghostscript, glusterfs, PackageKit, qpdf, and xen), Mageia (anki, libofx, ming, sox, webkit2, and xdg-user-dirs), Oracle (corosync, java-1.7.0-openjdk, and pcs), Red Hat (java-1.7.0-openjdk), Scientific Linux (corosync, firefox, gcc, glibc, golang, java-1.7.0-openjdk, java-1.8.0-openjdk, kernel, krb5, librelp, libvncserver, libvorbis, ntp, openssh, openssl, PackageKit, patch, pcs, policycoreutils, qemu-kvm, and xdg-user-dirs), Slackware (libwmf and mozilla), and Ubuntu (apache2, ghostscript, mysql-5.7, wavpack, and webkit2gtk).