New Spectre v2 Variant Exposes Intel, AMD, Arm CPUs to Data Leaks

Key Points:

• A new variant of the Spectre v2 attack, named Branch Target Reuse (BTR), has been disclosed, affecting Intel, AMD, and Arm CPUs. This vulnerability allows attackers to exploit just-in-time (JIT) compilers to leak sensitive data from memory.
• The impact includes potential data leaks of sensitive information such as password hashes from systems running Linux and browsers like Firefox. Exploits can bypass existing mitigations even on fully updated systems.
• Recommended actions include implementing software fixes such as indirect branch prediction barriers (IBPB) and enhancing site isolation in browsers to mitigate the risks associated with BTR.

Technical Details: The BTR attack exploits how modern CPUs handle indirect branch predictions after self-modification of code. It can leak data at a rate of 8 bytes per second by hijacking speculative execution.

MITRE ATT&CK Techniques:

• None mentioned

IOCs Mentioned:

• None mentioned