Vulnerability Description
Mongoose is an embedded web server and network library. Prior to 7.22, an attacker who can create a file with an HTML payload in its name can trigger stored cross-site scripting when a user browses a directory served with MG_ENABLE_DIRLIST. The printdirentry() path called by listdir() in src/http.c URL-encodes the href but inserts the raw filesystem filename into the HTML link text. The browser executes the injected markup in the Mongoose origin, which can expose session data or permit actions as the victim. This issue is fixed in version 7.22.
CVSS Score
MEDIUM
Related Weaknesses (CWE)
References
- https://github.com/cesanta/mongoose/commit/a9df523f76f43a38bd53b4232b9cfd4c16869
- https://github.com/cesanta/mongoose/pull/3611
- https://github.com/cesanta/mongoose/releases/tag/7.22
- https://github.com/cesanta/mongoose/security/advisories/GHSA-5g6j-m3pv-4f7g
- https://github.com/cesanta/mongoose/security/advisories/GHSA-5g6j-m3pv-4f7g
FAQ
What is CVE-2026-73254?
CVE-2026-73254 is a vulnerability with a CVSS score of 5.4 (MEDIUM). Mongoose is an embedded web server and network library. Prior to 7.22, an attacker who can create a file with an HTML payload in its name can trigger stored cross-site scripting when a user browses a ...
How severe is CVE-2026-73254?
CVE-2026-73254 has been rated MEDIUM with a CVSS base score of 5.4/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-73254?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.