Critical severity · published Jul 13, 2026
CVE-2026-40468
Heap buffer overflow in gawk
9.1
CVSS
0.2%
EPSS
No
On KEV
Description
Integer overflow vulnerability has been found in "builtin.c" program file of gawk. This issue may lead to memory exhaustion on the hosting operating system and could be used to overwrite gawk heap metadata and objects with attacker-controlled bytes. 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:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 10% 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-2026-40468
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-40468
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=062f2f2581b991362c046f7f2e238ffa34e6f8c7
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