XSS in Roundcube Webmail

CVE-2026-48849

In Roundcube Webmail 1.6.x before 1.6.16 and 1.7.x before 1.7.1, an unsanitized subject field in the draft restored value could lead to stored XSS/HTML/CSS injection on shared mailboxes.

Vulnerability class: XSS (Cross-Site Scripting)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 4.4 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.003 (16.1th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 16th percentile — 16.1% 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-2026-48849: held from 0.002 to 0.003.

EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.000

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2026-48849?
CVE-2026-48849 is a medium-severity vulnerability in Roundcube Webmail, classified under Cross-site Scripting. CVSS score: 4.4/10. Published 2026-05-25.
How severe is CVE-2026-48849?
Medium severity. CVSS v3 base score is 4.4 out of 10.
Is CVE-2026-48849 known to be exploited?
2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.