Critical Linux Kernel Flaws Expose Systems to Privilege Escalation and Data Leak
Multiple high-severity vulnerabilities in the Linux kernel affect various architectures and file systems. Attackers can exploit these flaws to leak sensitive data or escalate privileges.
TL;DR
- NTFS implementation in Linux kernel vulnerable to out-of-bounds read (CVE-2023-45896).
- AMD processors expose data via speculative execution flaw (CVE-2025-54505).
- Zen 2 CPUs allow privilege escalation through cache isolation failure (CVE-2025-54518).
- Kernel updates address flaws across ARM, x86, MIPS, PowerPC, S390, and block layer subsystems.
- Organizations using Intel IoTG kernels should apply patches immediately.
A set of critical vulnerabilities has been identified in the Linux kernel, particularly affecting Intel IoTG-based systems. These flaws span multiple subsystems and hardware architectures, enabling attackers to access sensitive kernel memory or escalate privileges.
The most notable issues include an NTFS file system vulnerability that allows out-of-bounds reads, speculative execution data leakage on certain AMD processors, and a cache isolation bypass affecting AMD Zen 2 chips. These weaknesses collectively pose significant risk to system integrity and confidentiality.
Ubuntu has released security updates addressing these issues. Organizations relying on affected kernel versions are strongly advised to patch their systems promptly to mitigate potential exploitation.
File System and Memory Exposure Risks
- CVE-2023-45896 affects the NTFS file system implementation, allowing an attacker to construct a malicious image that triggers an out-of-bounds read.
- Exploitation could lead to unauthorized access to kernel memory, potentially exposing cryptographic keys, passwords, or other sensitive data.
- Systems that mount untrusted NTFS volumes are especially at risk.
Hardware-Level Vulnerabilities in AMD Processors
- CVE-2025-54505 impacts some AMD processors where data in the floating point divider is not cleared during speculative execution, risking data leakage by local attackers.
- CVE-2025-54518 affects AMD Zen 2 processors due to improper shared resource isolation in the operation cache, which may enable lower-privilege users to corrupt higher-privilege instructions.
- Both processor-related flaws require local access but can result in full system compromise when chained with other vulnerabilities.
Widespread Kernel Subsystem Impacts
- Flaws were found across multiple CPU architectures: ARM32, ARM64, MIPS, PowerPC, S390, and x86.
- The block layer subsystem also contains exploitable conditions that could be used to compromise system stability or security.
- These systemic issues increase the attack surface across diverse computing environments running affected kernel versions.
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