CVE-2026-43178
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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.13%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
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.
- CVSS 3.1
- 7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 0.13% probability · 3th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-415, CWE-1341
- Affected
- linux/linux kernel
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/61dc9f776705d6db6847c101b98fa4f0e9eb6fa3Patch
- https://git.kernel.org/stable/c/8adaff87db143583e08eec4f4e7788f1ef8af94dPatch
- https://git.kernel.org/stable/c/90f5e87c9b75833b9ef3a4415b92c0247f28ab2fPatch
- https://git.kernel.org/stable/c/f9fe092084cd04deea18747f58a2304026e76aaaPatch
- https://access.redhat.com/security/cve/CVE-2026-43178
- https://bugzilla.redhat.com/show_bug.cgi?id=2467227
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-43178.json
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.