What’s Vulnerable › Vulnerabilities

CVE-2026-75004

• Severity: medium (CVSS 4.3 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.4% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-08-17 · updated 2026-09-08
• Weakness: CWE-77

Description

In Roundcube Webmail before 1.6.18 and 1.7.x before 1.7.3, improper rule name quoting could lead to managesieve_disabled_actions setting bypass via a crafted rule name in a Sieve script. This issue only affects Roundcube instances using the managesieve plugin.

Affected products

• Roundcube Webmail: from 1.6.0 before 1.6.18; from 1.7.0 before 1.7.3 — fixed in 1.6.18, 1.7.3

How to fix

Upgrade to a fixed version: Roundcube Webmail 1.6.18, 1.7.3. Check the vendor advisory for mitigations.

References

• https://github.com/roundcube/roundcubemail/releases/tag/1.6.18
• https://github.com/roundcube/roundcubemail/releases/tag/1.7.3
• https://roundcube.net/news/2026/08/09/security-updates-1.6.18-and-1.7.3

Get alerted when CVE-2026-75004 or the next vulnerability affects your stack