CVE-2026-54433
10.0
CRITICAL
CVSS 3.1
EPSS 0.31%
Description
In Roundcube Webmail before 1.6.17 and 1.7.x before 1.7.2, there is Stored Cross-Site Scripting (XSS) via a crafted plain-text email message. The attacker-controlled JavaScript executes within the victim's authenticated session simply by opening or previewing the message (zero-click).
How to fix CVE-2026-54433
No fixed version has been published yet. Mitigate by removing the affected package or applying upstream guidance from the references below.
- Debian/roundcube—no fix listed
Is CVE-2026-54433 being exploited?
Low — EPSS is 0.3%, meaning exploitation activity has not been observed at scale.
Affected packages (1)
- from 0
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | CRITICAL10.0 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N |