CISA KEV catalog
Confirmed active exploitation.
Listed in CISA's catalog of Known Exploited Vulnerabilities: attackers are using it in real attacks. Patch it with priority.
- Name
- RoundCube Webmail Cross-Site Scripting Vulnerability
- Added to catalog
- Remediation due date (US federal)
- Required action
- Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Description
A Cross-Site Scripting vulnerability in Roundcube through 1.5.7 and 1.6.x through 1.6.7 allows a remote attacker to steal and send emails of a victim via a crafted e-mail message that abuses a Desanitization issue in message_body() in program/actions/mail/show.php.
Affected products
roundcube: webmail
References6
- roundcube.net/news/2024/08/04/security-updates-1.6.8-and-1.5.8 Vendor Advisory
- github.com/roundcube/roundcubemail/releases Release Notes
- github.com/roundcube/roundcubemail/releases/tag/1.5.8 Release Notes
- github.com/roundcube/roundcubemail/releases/tag/1.6.8 Release Notes
- sonarsource.com/blog/government-emails-at-risk-critical-cross-s… Technical DescriptionThird Party Advisory
- www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=… US Government Resource
Metrics
- CVSS 3.1
-
9.3
CRITICAL
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N - EPSS — exploit probability
- 83% percentile: 100 · as of 3 November 2026
- CWE
- CWE-79
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