Vulnerability Description
Roundcube Webmail before 1.6.20 and 1.7.x before 1.7.5 is affected by an uncontrolled resource consumption vulnerability in the CSS proxy (the utils/modcss action). The fetched stylesheet was read into memory in full, with no size limit and no read timeout, so a stylesheet URL referencing an attacker-controlled host could be used to exhaust server memory. Upstream fixed this in the commit “Add a size limit to the CSS proxy content processing”, which caps the response at 5 MB, reads it as a stream and applies a read timeout.
CVSS Score
MEDIUM
Related Weaknesses (CWE)
References
- https://bugs.debian.org/1151279
- https://github.com/roundcube/roundcubemail/commit/2c9f6da692fa37cad2aaf85d5b127b
- https://github.com/roundcube/roundcubemail/commit/99a5bdd05b01f45493cc0da4c96968
- https://github.com/roundcube/roundcubemail/releases/tag/1.6.20
- https://github.com/roundcube/roundcubemail/releases/tag/1.7.5
- https://roundcube.net/news/2026/10/19/security-updates-1.6.20-and-1.7.5
FAQ
What is CVE-2026-114731?
CVE-2026-114731 is a vulnerability with a CVSS score of 5.3 (MEDIUM). Roundcube Webmail before 1.6.20 and 1.7.x before 1.7.5 is affected by an uncontrolled resource consumption vulnerability in the CSS proxy (the utils/modcss action). The fetched stylesheet was read int...
How severe is CVE-2026-114731?
CVE-2026-114731 has been rated MEDIUM with a CVSS base score of 5.3/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-114731?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.