CVE-2026-40553
Stack-based buffer overflow in gawk
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.
INFO
Published Date :
July 13, 2026, 1:16 p.m.
Last Modified :
July 13, 2026, 2:16 p.m.
Remotely Exploit :
No
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 4.0 | MEDIUM | 4bb8329e-dd38-46c1-aafb-9bf32bcb93c6 | ||||
| CVSS 4.0 | MEDIUM | [email protected] |
Solution
- Update gawk to version 5.4.1 or later.
- Recompile gawk with updated sources if applicable.
- Apply vendor patches for gawk.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-40553.
| URL | Resource |
|---|---|
| https://cert.pl/en/posts/2026/07/CVE-2026-40467 | |
| https://cgit.git.savannah.gnu.org/cgit/gawk.git/commit/?id=cca0366144336b49aaa7d5d949966ce8e2c70843 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-40553 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-40553
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-40553 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-40553 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jul. 13, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-40553', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-07-13T13:00:40.324542Z'} -
New CVE Received by [email protected]
Jul. 13, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://cgit.git.savannah.gnu.org/cgit/gawk.git/', 'vendor': 'GNU', 'product': 'gawk', 'versions': [{'status': 'affected', 'version': '0', 'versionType': 'semver', 'lessThanOrEqual': '5.4.0'}], 'programFiles': ['readdir.c'], 'defaultStatus': 'unaffected', 'programRoutines': [{'name': 'ftype()'}]}] Added 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. Added CVSS V4.0 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 Added CWE CWE-121 Added Reference https://cert.pl/en/posts/2026/07/CVE-2026-40467 Added Reference https://cgit.git.savannah.gnu.org/cgit/gawk.git/commit/?id=cca0366144336b49aaa7d5d949966ce8e2c70843