Security News
AMD has started issuing some patches for its processors affected by a serious silicon-level bug dubbed Zenbleed that can be exploited by rogue users and malware to steal passwords, cryptographic keys, and other secrets from software running on a vulnerable system. Exploiting Zenbleed involves abusing speculative execution, though unlike the related Spectre family of design flaws, the bug is pretty easy to exploit.
After a long break, AMD has released a new graphics driver, Adrenalin 23.7.1 WHQL. The new driver supports additional Vulkan extensions and introduces numerous fixes, although some known issues remain unresolved. The driver update has also addressed an application crash or driver timeout that users could experience when playing AV1 video content using DaVinci Resolve Studio.
Three vulnerabilities in the American Megatrends MegaRAC Baseboard Management Controller software impact server equipment used in many cloud service and data center providers. The flaws were discovered by Eclypsium in August 2022 and could enable attackers, under certain conditions, to execute code, bypass authentication, and perform user enumeration.
A group of researchers has revealed details of a new vulnerability affecting Intel CPUs that enables attackers to obtain encryption keys and other secret information from the processors. "The scan of the I/O address space on Intel CPUs based on the Sunny Cove microarchitecture revealed that the memory-mapped registers of the local Advanced Programmable Interrupt Controller are not properly initialized," the researchers noted.
Retbleed is also the latest addition to a class of Spectre attacks known as Spectre-BTI, which exploit the side effects of an optimization technique called speculative execution by means of a timing side channel to trick a program into accessing arbitrary locations in its memory space and leak private information. Speculative execution attempts to fill the instruction pipeline of a program by predicting which instruction will be executed next in order to gain a performance boost, while also undoing the results of the execution should the guess turn out to be wrong.
Older AMD and Intel chips are vulnerable to yet another Spectre-based speculative-execution attack that exposes secrets within kernel memory despite defenses already in place. "Unlike its siblings, who trigger harmful branch target speculation by exploiting indirect jumps or calls, Retbleed exploits return instructions," explained Wikner and Razavi in a draft blog post about the design bug provided to The Register.
Semiconductor giant AMD says they are investigating a cyberattack after the RansomHouse gang claimed to have stolen 450 GB of data from the company last year. RansomHouse is a data extortion group that breaches corporate networks, steals data, and then demands a ransom payment to not publicly leak the data or sell it to other threat actors.
If claims hold true, AMD has been targeted by the extortion group RansomHouse, which says it is sitting on a trove of data stolen from the processor designer following an alleged security breach earlier this year. The data was stolen from AMD in January, according to the group.
A newly discovered security vulnerability in modern Intel and AMD processors could let remote attackers steal encryption keys via a power side channel attack. This can have significant security implications on cryptographic libraries even when implemented correctly as constant-time code to prevent timing-based side channels, effectively enabling an attacker to leverage the execution time variations to extract sensitive information such as cryptographic keys.
A new side-channel attack known as Hertzbleed allows remote attackers to steal full cryptographic keys by observing variations in CPU frequency enabled by dynamic voltage and frequency scaling. "In the worst case, these attacks can allow an attacker to extract cryptographic keys from remote servers that were previously believed to be secure. [.] Hertzbleed is a real, and practical, threat to the security of cryptographic software," the security researchers explain.