Vulnerability in Roundcube Webmail

CVE-2026-26079

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.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 4.7 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N.

EPSS exploit prediction

EPSS: 0.005 (41.5th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 41st percentile — 41.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-26079: held from 0.003 to 0.005.

EPSS over last 30 days · oldest: 0.003 · newest: 0.005 · change: +0.002

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-26079?
CVE-2026-26079 is a medium-severity vulnerability in Roundcube Webmail, classified under Inclusion of Functionality from Untrusted Control Sphere. CVSS score: 4.7/10. Published 2026-02-11.
How severe is CVE-2026-26079?
Medium severity. CVSS v3 base score is 4.7 out of 10.