CVE-2026-40553: fossies gawk Stack-based Buffer Overflow
CVSS: 7.5v3.1HighAnalyzed
AliasesUBUNTU-CVE-2026-40553DEBIAN-CVE-2026-40553
Published 13-07-2026Last modified 13-07-2026
Vulnerability summary
CVE-2026-40553 is a high (CVSS 7.5) Stack-based Buffer Overflow vulnerability in fossies gawk. EPSS estimates a 0.29% chance of exploitation in the next 30 days, higher than 20.3% of scored vulnerabilities.
CVSS score
7.5/10
010
High · v3.1 (NVD)EPSS score
0.29%
0%100%
Low · 0.00 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded
Advisory lineage
Upstream 0 · Downstream 11 · Related 6Timeline
- 13-07-2026PublishedVulnerability first disclosed.
- 13-07-2026Last modifiedVulnerability information updated.
Description
Buffer overflow vulnerability has been found in "extension/readdir.c" program file of gawk (ftype() routine). This issue could be used to crash the program and potentially to achieve code execution, although the latter has not been confirmed to be feasible. It affects gawk in versions 5.4.0 and below.
CVSS metrics
6 scores · 4 sources · 2 versionsMedium 5.1Preferred score · CVE.org (CNA)
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:L/SI:L/SA:LSourcesAll 3 agree
- OSV · UbuntuEcosystem advisory · calculated5.1MediumCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:L/SI:L/SA:L
- NVDNIST5.1MediumCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:L/SI:L/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
High 7.5Preferred score · NVD (NIST)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HSourcesAll 3 agree
- OSV · UbuntuEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
0.29%
Chance of exploitation in the next 30 days
Percentile
20%
Versus all other CVEs
30-day change
0.00 pp
From 0.29% on 20-09-2026
20-09-202620-10-2026
EPSS score0.29%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Debian1 product
- gawkAll versions (No fix recorded)
Fossies1 product
- gawk≤ 5.4.0
Gnu1 product
- gawk≤ 5.4.0
Ubuntu1 product
- gawk< 1:5.3.2-1ubuntu1.1
4 vendors · 4 products
References
7 links- cert.pl/en/posts/2026/07/CVE-2026-40467Third Party Advisory
