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. 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 v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

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

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel:6.19:-::::::

History

No history.

Information

Published : 2026-05-06 12:16

Updated : 2026-07-15 02:21

NVD link : CVE-2026-43178

Mitre link : CVE-2026-43178

CVE.ORG link : CVE-2026-43178

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-415

Double Free

CWE-1341

Multiple Releases of Same Resource or Handle

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buffer for build ID for PROCMAP_QUERY\nwe return with -ENAMETOOLONG error. After recent changes this condition\nhappens later, after we unlocked mmap_lock/per-VMA lock and did mmput(),\nso original goto out is now wrong and will double-mmput() mm_struct. Fix\nby jumping further to clean up only vm_file and name_buf."}], "lastModified": "2026-07-15T02:21:42.640", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "8A635070-FE03-4A8C-B47E-AD467AF0ECB5", "versionEndExcluding": "6.12.75", "versionStartIncluding": "6.12.70"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "A9F81ACF-F1AC-4BC9-9659-E4262A27E733", "versionEndExcluding": "6.18.16", "versionStartIncluding": "6.18.10"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "4AD214F0-0792-4904-85C0-348C7DE41227", "versionEndExcluding": "6.19.6", "versionStartIncluding": "6.19.1"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.19:-:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "35C8A871-4971-433E-A046-FC9F7B7D190A"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}