What’s Vulnerable › Vulnerabilities

CVE-2026-26079

• Severity: medium (CVSS 4.7 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.3% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-02-11 · updated 2026-06-17
• Weakness: CWE-829

Description

Roundcube Webmail before 1.5.13 and 1.6 before 1.6.13 allows Cascading Style Sheets (CSS) injection, e.g., because comments are mishandled.

Affected products

• Roundcube Webmail: before 1.5.13; from 1.6.0 before 1.6.13 — fixed in 1.5.13, 1.6.13

How to fix

Upgrade to a fixed version: Roundcube Webmail 1.5.13, 1.6.13. Check the vendor advisory for mitigations.

References

• https://github.com/roundcube/roundcubemail/commit/1f4c3a5af5033747f9685a8a395dbd8228d19816
• https://github.com/roundcube/roundcubemail/commit/2b5625f1d2ef7e050fd1ae481b2a52dc35466447
• https://github.com/roundcube/roundcubemail/commit/53d75d5dfebef235a344d476b900c20c12d52b01
• https://github.com/roundcube/roundcubemail/commit/5a3315cce587e0be58335d11ff9a5571c90494a5
• https://github.com/roundcube/roundcubemail/commit/bf89cbaa5897d8ad62e8057d9a3f6babb90b7954
• https://github.com/roundcube/roundcubemail/commit/c15f5dbf093a497e19a749b20e7f8fb5a9c24cde
• https://github.com/roundcube/roundcubemail/releases/tag/1.5.13
• https://github.com/roundcube/roundcubemail/releases/tag/1.6.13
• https://roundcube.net/news/2026/02/08/security-updates-1.6.13-and-1.5.13

Get alerted when CVE-2026-26079 or the next vulnerability affects your stack