CVE-2026-54432 Cross-site scripting in Webmail
Attackers can inject malicious scripts via attachment MIME types, potentially stealing user sessions or executing code in Roundcube Webmail.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-54432?
CVE-2026-54432 is a medium-severity cross-site scripting vulnerability in Roundcube Webmail, published on 14 Jul 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
Roundcube Webmail before 1.6.17 and 1.7.x before 1.7.2 allows Stored Cross-Site Scripting (XSS). The issue occurs because the attachment MIME type is not properly escaped on the attachment-validation warning page.
Weakness: CWE-79
Which versions are affected by CVE-2026-54432?
How do I fix CVE-2026-54432?
Upgrade to a fixed version.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2026-54432 being exploited?
There is no known exploitation of CVE-2026-54432 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-54432, GHSA-w8fm-hrh6-r2j7, UBUNTU-CVE-2026-54432.