High 7.8Published May 6, 2026

CVE-2026-43178procfs: fix possible double mmput() in do_procmap_query()

Updated under an hour ago (Oct 27, 2026, 3:23 AM ET)

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Exploited in the last 30 days

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: 7.8 HIGH (v3.1, CNA)CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Weakness (CWE): CWE-1341
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Linux
NVD analysis: Modified
Record last updated: Aug 5, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Linux Linux linux:linux (from the name)	from b9b97e6aeb534315f9646b2090d1a5024c6a4e82 before f9fe092084cd04deea18747f58a2304026e76aaa; from cbc03ce3e6ce7e21214c3f02218213574c1a2d08 before 8adaff87db143583e08eec4f4e7788f1ef8af94d; from b5cbacd7f86f4f62b8813688c8e73be94e8e1951 before 90f5e87c9b75833b9ef3a4415b92c0247f28ab2f; from b5cbacd7f86f4f62b8813688c8e73be94e8e1951 before 61dc9f776705d6db6847c101b98fa4f0e9eb6fa3; from 6.12.70 before 6.12.75; from 6.18.10 before 6.18.16	CNA record
Red Hat Red Hat Enterprise Linux 10 redhat:enterprise_linux	10	CISA ADP
linux linux_kernel linux:linux_kernel	from 6.12.70 before 6.12.75; from 6.18.10 before 6.18.16; from 6.19.1 before 6.19.6; 6.19	NVD

References

References

https://git.kernel.org/stable/c/f9fe092084cd04deea18747f58a2304026e76aaa	patch
https://git.kernel.org/stable/c/8adaff87db143583e08eec4f4e7788f1ef8af94d	patch
https://git.kernel.org/stable/c/90f5e87c9b75833b9ef3a4415b92c0247f28ab2f	patch
https://git.kernel.org/stable/c/61dc9f776705d6db6847c101b98fa4f0e9eb6fa3	patch
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

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.