CVE WatchJul 30, 2026

CVE-2025-39902

In the Linux kernel, the following vulnerability has been resolved: mm/slub: avoid accessing metadata when pointer is invalid in object_err

CVSS

7.1

High

EPSS

0.1%

KEV

—

Exploit Today

0-100

Published: Oct 1, 2025 · Last modified: Jul 30, 2026 · CWE-476

EPSS · 30d

0.1%EPSS · 30 days0.1%

2026-07-022026-07-29

Technical description

In the Linux kernel, the following vulnerability has been resolved: mm/slub: avoid accessing metadata when pointer is invalid in object_err() object_err() reports details of an object for further debugging, such as the freelist pointer, redzone, etc. However, if the pointer is invalid, attempting to access object metadata can lead to a crash since it does not point to a valid object. One known path to the crash is when alloc_consistency_checks() determines the pointer to the allocated object is invalid because of a freelist corruption, and calls object_err() to report it. The debug code should report and handle the corruption gracefully and not crash in the process. In case the pointer is NULL or check_valid_pointer() returns false for the pointer, only print the pointer value and skip accessing metadata.

Official references

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