High severity · published May 6, 2026
CVE-2026-43178
procfs: fix possible double mmput() in do_procmap_query()
7.8
CVSS
0.1%
EPSS
No
On KEV
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 vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.1% · higher than 3% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KE
Kernel · Linux
6.12.70 before 6.12.75; 6.18.10 before 6.18.16; 6.19.1 before 6.19.6; 6.19 · source: NVD
LI
Linux · Linux
b9b97e6aeb534315f9646b2090d1a5024c6a4e82 before f9fe092084cd04deea18747f58a2304026e76aaa; cbc03ce3e6ce7e21214c3f02218213574c1a2d08 before 8adaff87db143583e08eec4f4e7788f1ef8af94d; b5cbacd7f86f4f62b8813688c8e73be94e8e1951 before 90f5e87c9b75833b9ef3a4415b92c0247f28ab2f; b5cbacd7f86f4f62b8813688c8e73be94e8e1951 before 61dc9f776705d6db6847c101b98fa4f0e9eb6fa3; 6.12.70 before 6.12.75; 6.18.10 before 6.18.16; +1 more · source: vendor
RH
Red Hat Enterprise Linux 6 · Red Hat
All versions, or not specified · source: CISA
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-43178
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-43178
Patch
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
access.redhat.com
https://access.redhat.com/security/cve/CVE-2026-43178
bugzilla.redhat.com
https://bugzilla.redhat.com/show_bug.cgi?id=2467227
More from Kernel
9.8
CVE-2025-39682
tls: fix handling of zero-length records on the rx_list
8.8
CVE-2026-53266
netfilter: bridge: make ebt_snat ARP rewrite writable
8.8
CVE-2013-6282
Linux Kernel Improper Input Validation Vulnerability
8.4
CVE-2022-0185
Linux Kernel Heap-Based Buffer Overflow Vulnerability
8.4
CVE-2013-2094
Linux Kernel Privilege Escalation Vulnerability
