High severity · published Jul 13, 2026
CVE-2026-40467
Use after free in gawk
7.5
CVSS
0.2%
EPSS
No
On KEV
Description
Use After Free vulnerability has been found in "io.c" program file of gawk (do_getline_redir() routine). This issue may lead to a crash. It affects gawk in versions 5.4.0 and below.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 12% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
GA
gawk · GNU
through 5.4.0 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-40467
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-40467
Third Party Advisory
https://cert.pl/en/posts/2026/07/CVE-2026-40467
Patch
https://cgit.git.savannah.gnu.org/cgit/gawk.git/commit/?id=a2d18c74109e41bec29a23098eba2e00057286d8
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