CVE Catalog

CVE-2026-43178

HighCVSS 7.8
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.13%

3th percentile - higher than 3% of all known CVEs

Summary

In the Linux kernel, a vulnerability in the do_procmap_query() function in procfs can cause a double mmput() on the mm_struct. The issue occurs when a user provides an incorrectly sized buffer for the build ID, triggering an -ENAMETOOLONG error after locks are released and mmput() is called, leading to a second mmput() in the error path.

Risk Assessment

A double reference release on mm_struct can cause kernel memory corruption, potentially allowing a local attacker to trigger a system crash (kernel panic) or escalate privileges.

Recommendation

Immediately update the Linux kernel to a version containing the fix (commit that jumps to the appropriate cleanup label). If updating is not possible, restrict access to the PROCMAP_QUERY interface for unprivileged users.

Other vulnerabilities in Linux kernel

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Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: procfs: fix possible double mmput() in do_procmap_query() When user provides incorrectly sized buffer for build ID for PROCMAP_QUERY we return with -ENAMETOOLONG error. After recent changes this condition happens later, after we unlocked mmap_lock/per-VMA lock and did mmput(), so original goto out is now wrong and will double-mmput() mm_struct. Fix by jumping further to clean up only vm_file and name_buf.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS