CVE-2026-40468: "builtin.c" program file of gawk · Integer Overflow Vulnerability Has Been Found
Affects gawkSource GCVE Database
Not known to be exploited · CVSS 2.1 Low.
Data as of 26 Oct 2026, 10:12 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 9% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:LExploitation evidence
Disclosed: evidence found.
CVE published 13 Jul 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSgawkpkg:deb/ubuntu/gawk@1:5.3.2-1ubuntu1?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSgawkpkg:deb/ubuntu/gawk@1:5.2.1-2build3?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 22.04 LTSgawkpkg:deb/ubuntu/gawk@1:5.1.0-1ubuntu0.1?arch=source&distro=jammyOther threats | Affected
| Fixed in– |
Ubuntu 20.04 LTSgawkpkg:deb/ubuntu/gawk@1:5.0.1+dfsg-1ubuntu0.1?arch=source&distro=focalOther threats | Affected
| Fixed in– |
Ubuntu Pro 18.04 LTSgawkpkg:deb/ubuntu/gawk@1:4.1.4+dfsg-1ubuntu0.1~esm1?arch=source&distro=esm-infra/bionicOther threats | Affected
| Fixed in– |
Ubuntu Pro 16.04 LTSgawkpkg:deb/ubuntu/gawk@1:4.1.3+dfsg-0.1ubuntu0.1~esm1?arch=source&distro=esm-infra/xenialOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Until a fix is available, avoid processing untrusted input with vulnerable gawk versions.
Description
An integer overflow vulnerability exists in the builtin.c file of gawk versions 5.4.0 and below. This flaw can cause memory exhaustion on the host operating system and may allow an attacker to overwrite gawk heap metadata and objects with controlled data. The issue affects multiple specific gawk package versions, primarily on Ubuntu distributions. No exploit in the wild has been reported.