Tag Archives: sensors

Side Channels Are Common

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2024/01/side-channels-are-common.html

Really interesting research: “Lend Me Your Ear: Passive Remote Physical Side Channels on PCs.”

Abstract:

We show that built-in sensors in commodity PCs, such as microphones, inadvertently capture electromagnetic side-channel leakage from ongoing computation. Moreover, this information is often conveyed by supposedly-benign channels such as audio recordings and common Voice-over-IP applications, even after lossy compression.

Thus, we show, it is possible to conduct physical side-channel attacks on computation by remote and purely passive analysis of commonly-shared channels. These attacks require neither physical proximity (which could be mitigated by distance and shielding), nor the ability to run code on the target or configure its hardware. Consequently, we argue, physical side channels on PCs can no longer be excluded from remote-attack threat models.

We analyze the computation-dependent leakage captured by internal microphones, and empirically demonstrate its efficacy for attacks. In one scenario, an attacker steals the secret ECDSA signing keys of the counterparty in a voice call. In another, the attacker detects what web page their counterparty is loading. In the third scenario, a player in the Counter-Strike online multiplayer game can detect a hidden opponent waiting in ambush, by analyzing how the 3D rendering done by the opponent’s computer induces faint but detectable signals into the opponent’s audio feed.

Breaking Laptop Fingerprint Sensors

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2023/11/breaking-laptop-fingerprint-sensors.html

They’re not that good:

Security researchers Jesse D’Aguanno and Timo Teräs write that, with varying degrees of reverse-engineering and using some external hardware, they were able to fool the Goodix fingerprint sensor in a Dell Inspiron 15, the Synaptic sensor in a Lenovo ThinkPad T14, and the ELAN sensor in one of Microsoft’s own Surface Pro Type Covers. These are just three laptop models from the wide universe of PCs, but one of these three companies usually does make the fingerprint sensor in every laptop we’ve reviewed in the last few years. It’s likely that most Windows PCs with fingerprint readers will be vulnerable to similar exploits.

Details.

Smartphones and Civilians in Wartime

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2022/06/smartphones-and-civilians-in-wartime.html

Interesting article about civilians using smartphones to assist their militaries in wartime, and how that blurs the important legal distinction between combatants and non-combatants:

The principle of distinction between the two roles is a critical cornerstone of international humanitarian law­—the law of armed conflict, codified by decades of customs and laws such as the Geneva Conventions. Those considered civilians and civilian targets are not to be attacked by military forces; as they are not combatants, they should be spared. At the same time, they also should not act as combatants—­if they do, they may lose this status.

The conundrum, then, is how to classify a civilian who, with the use of their smartphone, potentially becomes an active participant in a military sensor system. (To be clear, solely having the app installed is not sufficient to lose the protected status. What matters is actual usage.) The Additional Protocol I to Geneva Conventions states that civilians enjoy protection from the “dangers arising from military operations unless and for such time as they take a direct part in hostilities.” Legally, if civilians engage in military activity, such as taking part in hostilities by using weapons, they forfeit their protected status, “for such time as they take a direct part in hostilities” that “affect[s] the military operations,” according to the International Committee of the Red Cross, the traditional impartial custodian of International Humanitarian Law. This is the case even if the people in question are not formally members of the armed forces. By losing the status of a civilian, one may become a legitimate military objective, carrying the risk of being directly attacked by military forces.