Fossies Gawk
Fossies Gawk has a recently disclosed critical-severity vulnerability (CVE-2026-40469). It has not been reported as actively exploited — patch it proactively as part of your normal cycle before that changes.
What is this vulnerability?
Integer overflow vulnerability has been found in "builtin.c" program file of gawk (do_sub() routine). This issue could be used to overwrite gawk heap metadata and objects causing the program to crash. It affects 32-bit builds of gawk in versions 5.4.0 and below.
How it works
This is classified as Integer Overflow. In plain terms, an attacker could use this flaw in Gawk to gain access, disrupt service, or steal data — the exact impact depends on how it’s deployed in your environment.
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
Mitigations
- Apply the vendor’s security patch or update as soon as it’s available and tested.
- If no patch exists yet, apply the vendor’s temporary workaround.
- Limit network exposure of the affected system until it’s patched.
- Track the vendor advisory — disclosed vulnerabilities can move to active exploitation quickly.
Recommendations
- Confirm whether Fossies Gawk is used anywhere in your environment.
- Patch internet-facing systems first, then internal ones.
- Prioritise by exposure and exploitability while a fix is scheduled.
- Subscribe to the vendor’s security advisories for earlier warning next time.
Compiled from the National Vulnerability Database (NVD), referenced in 2 public advisories. Listed as recently disclosed — not confirmed exploited.