CVE-2026-35538 Roundcube Webmail: Unsanitized IMAP SEARCH command arguments

Low 3.1 Published 3 Apr 2026 Updated 3 Apr 2026

Attackers can inject IMAP commands or bypass CSRF protections during mail search in Roundcube Webmail, potentially accessing unauthorized data.

Exploited in the wild: Not known
Login needed: Any signed-in user
Attackable: Over the internet
Victim action needed: Not needed
Fix: Available

What is CVE-2026-35538?

CVE-2026-35538 is a low-severity vulnerability in Roundcube Webmail, published on 3 Apr 2026. Any signed-in user can exploit it over the network, with no action from the victim.

Official description

An issue was discovered in Roundcube Webmail before 1.5.14 and 1.6.14. Unsanitized IMAP SEARCH command arguments could lead to IMAP injection or CSRF bypass during mail search.

Weakness: CWE-88

Which versions are affected by CVE-2026-35538?

2 open source packages ship an affected version, including roundcube/roundcubemail. It affects 1 product.

Package	Affected	Fixed in
`roundcube/roundcubemail` Packagist	From `1.7-beta`	`1.7-rc5`
`roundcube/roundcubemail` Packagist	From `1.7-beta`	`1.7-rc5`

Products include Roundcube Webmail.

How do I fix CVE-2026-35538?

Upgrade roundcube/roundcubemail to 1.7-rc5 or later.

Is CVE-2026-35538 being exploited?

There is no known exploitation of CVE-2026-35538 in the wild and no public exploit code.

All Roundcube Webmail vulnerabilities

Sources

Also known as DEBIAN-CVE-2026-35538, GHSA-8jr8-v43g-5c57, UBUNTU-CVE-2026-35538.