CVE-2026-74999 Cross-site scripting in Webmail
Attackers can inject malicious scripts via the address book feature, potentially stealing user sessions or executing code in victim browsers.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-74999?
CVE-2026-74999 is a medium-severity cross-site scripting vulnerability in Roundcube Webmail, published on 17 Aug 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official description
In Roundcube Webmail before 1.6.18 and 1.7.x before 1.7.3, the "Add to address book" action was subject to stored XSS.
Weakness: CWE-79
Which versions are affected by CVE-2026-74999?
It affects 1 product.
Products include Roundcube Webmail.
How do I fix CVE-2026-74999?
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-2026-74999 being exploited?
There is no known exploitation of CVE-2026-74999 in the wild and no public exploit code.
Other vulnerabilities in Roundcube Webmail
Sources
Also known as DEBIAN-CVE-2026-74999, GHSA-pq94-h2h7-x49p, UBUNTU-CVE-2026-74999.