AMD | Breaking Cybersecurity News | The Hacker News

More than six years after the Spectre security flaw impacting modern CPU processors came to light, new research has found that the latest AMD and Intel processors are still susceptible to speculative execution attacks. The attack, disclosed by ETH Zürich researchers Johannes Wikner and Kaveh Razavi, aims to undermine the Indirect Branch Predictor Barrier ( IBPB ) on x86 chips, a crucial mitigation against speculative execution attacks. Speculative execution refers to a performance optimization feature wherein modern CPUs execute certain instructions out-of-order by predicting the branch a program will take beforehand, thus speeding up the task if the speculatively used value was correct. If it results in a misprediction, the instructions, called transient, are declared invalid and squashed, before the processor can resume execution with the correct value. While the execution results of transient instructions are not committed to the architectural program state, it's still ...

Researchers have discovered two novel attack methods targeting high-performance Intel CPUs that could be exploited to stage a key recovery attack against the Advanced Encryption Standard (AES) algorithm. The techniques have been collectively dubbed  Pathfinder  by a group of academics from the University of California San Diego, Purdue University, UNC Chapel Hill, Georgia Institute of Technology, and Google. "Pathfinder allows attackers to read and manipulate key components of the branch predictor, enabling two main types of attacks: reconstructing program control flow history and launching high-resolution Spectre attacks," Hosein Yavarzadeh, the lead author of the  paper , said in a statement shared with The Hacker News. "This includes extracting secret images from libraries like libjpeg and recovering encryption keys from AES through intermediate value extraction." Spectre is the name given to a  class of side-channel attacks ...

Vulnerability Management (VM) has long been a cornerstone of organizational cybersecurity. Nearly as old as the discipline of cybersecurity itself, it aims to help organizations identify and address potential security issues before they become serious problems. Yet, in recent years, the limitations of this approach have become increasingly evident.  At its core, Vulnerability Management processes remain essential for identifying and addressing weaknesses. But as time marches on and attack avenues evolve, this approach is beginning to show its age. In a recent report, How to Grow Vulnerability Management into Exposure Management (Gartner, How to Grow Vulnerability Management Into Exposure Management, 8 November 2024, Mitchell Schneider Et Al.), we believe Gartner® addresses this point precisely and demonstrates how organizations can – and must – shift from a vulnerability-centric strategy to a broader Exposure Management (EM) framework. We feel it's more than a worthwhile read an...

Cybersecurity researchers from ETH Zurich have developed a new variant of the RowHammer DRAM (dynamic random-access memory) attack that, for the first time, successfully works against AMD Zen 2 and Zen 3 systems despite mitigations such as Target Row Refresh (TRR). "This result proves that AMD systems are equally vulnerable to Rowhammer as Intel systems, which greatly increases the attack surface, considering today's AMD market share of around 36% on x86 desktop CPUs," the researchers  said . The technique has been codenamed  ZenHammer , which can also trigger RowHammer bit flips on DDR5 devices for the first time. RowHammer , first publicly disclosed in 2014, is a  well-known attack  that exploits DRAM's memory cell architecture to alter data by repeatedly accessing a specific row (aka hammering) to cause the electrical charge of a cell to leak to adjacent cells. This can induce random bit flips in neighboring memory rows (from 0 to 1, or vice versa), which can...

Researchers from the Vrije Universiteit Amsterdam have disclosed a new side-channel attack called  SLAM  that could be exploited to leak sensitive information from kernel memory on current and upcoming CPUs from Intel, AMD, and Arm. The attack is an end-to-end exploit for Spectre based on a new feature in Intel CPUs called  Linear Address Masking  ( LAM ) as well as its analogous counterparts from AMD (called  Upper Address Ignore  or  UAI ) and Arm (called  Top Byte Ignore  or  TBI ). "SLAM exploits unmasked gadgets to let a userland process leak arbitrary ASCII kernel data," VUSec researchers  said , adding it could be leveraged to leak the root password hash within minutes from kernel memory. While LAM is presented as a security feature, the study found that it ironically degrades security and "dramatically" increases the  Spectre attack surface , resulting in a transient execution attack, which exploits  speculati...

Intel has released fixes to close out a high-severity flaw codenamed  Reptar  that impacts its desktop, mobile, and server CPUs. Tracked as  CVE-2023-23583  (CVSS score: 8.8), the  issue  has the potential to "allow escalation of privilege and/or information disclosure and/or denial of service via local access." Successful exploitation of the vulnerability could also permit a bypass of the CPU's security boundaries, according to Google Cloud, which described it as an issue stemming from how redundant prefixes are interpreted by the processor. "The impact of this vulnerability is demonstrated when exploited by an attacker in a multi-tenant virtualized environment, as the exploit on a guest machine causes the host machine to crash resulting in a Denial of Service to other guest machines running on the same host," Google Cloud's Phil Venables  said . "Additionally, the vulnerability could potentially lead to information disclosure or privilege escal...

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. Dubbed  ÆPIC Leak , the weakness is the first-of-its-kind to architecturally disclose sensitive data in a manner that's akin to an "uninitialized memory read in the CPU itself." "In contrast to transient execution attacks like  Meltdown and Spectre ,  ÆPIC Leak  is an architectural bug: the sensitive data gets directly disclosed without relying on any (noisy) side channel," the academics said. The study was conducted by researchers from the Sapienza University of Rome, the Graz University of Technology, Amazon Web Services, and the CISPA Helmholtz Center for Information Security. The vulnerability ( CVE-2022-21233 , CVSS score: 6.0), which affects CPUs with Sunny Cover microarchitecture, is rooted in a component called Advanced Programmable Interrupt Controller ( APIC ), wh...

With speculative execution attacks remaining a stubbornly persistent vulnerability ailing modern processors, new research has highlighted an "industry failure" to adopt mitigations released by AMD and Intel, posing a firmware supply chain threat. Dubbed  FirmwareBleed  by Binarly, the information leaking assaults stem from the continued exposure of microarchitectural attack surfaces on the part of enterprise vendors either as a result of not correctly incorporating the fixes or only using them partially. "The impact of such attacks is focused on disclosing the content from privileged memory (including protected by virtualization technologies) to obtain sensitive data from processes running on the same processor (CPU)," the firmware protection firm  said  in a report shared with The Hacker News. "Cloud environments can have a greater impact when a physical server can be shared by multiple users or legal entities." In recent years, implementations of sp...

A newly discovered security vulnerability in modern Intel and AMD processors could let remote attackers steal encryption keys via a power side channel attack. Dubbed  Hertzbleed  by a group of researchers from the University of Texas, the University of Illinois Urbana-Champaign, and the University of Washington, the issue is rooted in dynamic voltage and frequency scaling ( DVFS ), a power and thermal management feature employed to conserve power and reduce the amount of heat generated by a chip. "The cause is that, under certain circumstances, periodic CPU frequency adjustments depend on the current CPU power consumption, and these adjustments directly translate to execution time differences (as 1 hertz = 1 cycle per second)," the researchers said. 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 t...