PT-2025-46597 · Linux+2 · Linux Kernel+2

Published

2025-08-20

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Updated

2026-02-24

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CVE-2025-40122

CVSS v2.0

4.0

Medium

VectorAV:A/AC:H/Au:S/C:P/I:P/A:P
Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)
Description The Linux kernel contains a flaw related to Model Specific Registers (MSRs) access during performance monitoring. Specifically, an incorrect check in the intel pmu acr late setup() helper function can lead to an invalid ACR counter mask being set, potentially triggering a General Protection (#GP) fault when writing to the IA32 PMC x CFG B MSRs. This issue occurs when running perf fuzzer on PTL systems, particularly with GP counters that do not support auto counter reload. The root cause is a typo in the check condition, and the issue can be triggered when a user creates a performance event with an incorrect ACR counter mask. The incorrect mask can lead to scheduling events on hardware counters that do not support the ACR feature, resulting in an MSR access error.
Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Exploit

RCE

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Weakness Enumeration

Related Identifiers

BDU:2025-15299
CVE-2025-40122
USN-8029-1
USN-8029-2
USN-8029-3
USN-8030-1
USN-8048-1

Affected Products

Linuxmint
Linux Kernel
Ubuntu