RoundCube Webmail Deserialization of Untrusted Data Vulnerability

[ Why it matters ]Priority signals

• Exploited in the wild: on CISA's Known Exploited Vulnerabilities list since 2026-02-20
• EPSS: 99% chance of exploitation in the next 30 days (higher than 100% of CVEs)

[ Description ]Official description

Roundcube Webmail before 1.5.10 and 1.6.x before 1.6.11 allows remote code execution by authenticated users because the _from parameter in a URL is not validated in program/actions/settings/upload.php, leading to PHP Object Deserialization.

CISA: RoundCube Webmail contains a deserialization of untrusted data vulnerability that allows remote code execution by authenticated users because the _from parameter in a URL is not validated in program/actions/settings/upload.php.

[ Fixes ]Fixes and patches

CISA required action (US federal deadline 13 Mar 2026): Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

• Patch on github.comVendor patch or bulletin · NVD · Reference tagged 'Patch' by NVD
• Patch on github.comVendor patch or bulletin · NVD · Reference tagged 'Patch' by NVD
• Patch on github.comVendor patch or bulletin · NVD · Reference tagged 'Patch' by NVD

[ References ]References

• fearsoff.org/research/roundcubeThird Party Advisory
• github.com/roundcube/roundcubemail/commit/0376f69e958a8fef7f6f09e352c541b4e7729c4dPatch
• github.com/roundcube/roundcubemail/commit/7408f31379666124a39f9cb1018f62bc5e2dc695Patch
• github.com/roundcube/roundcubemail/commit/c50a07d88ca38f018a0f4a0b008e9a1deb32637ePatch
• github.com/roundcube/roundcubemail/pull/9865Issue Tracking
• github.com/roundcube/roundcubemail/releases/tag/1.5.10Release Notes
• github.com/roundcube/roundcubemail/releases/tag/1.6.11Release Notes
• roundcube.net/news/2025/06/01/security-updates-1.6.11-and-1.5.10Vendor Advisory
• www.vicarius.io/vsociety/posts/cve-2025-49113-roundcube-mitigation-scriptExploitMitigationThird Party Advisory
• www.vicarius.io/vsociety/posts/cve-2025-49113-roundcube-vulnerability-detectionExploitMitigationThird Party Advisory
• www.openwall.com/lists/oss-security/2025/06/02/3Mailing ListThird Party Advisory
• lists.debian.org/debian-lts-announce/2025/06/msg00008.htmlMailing ListThird Party Advisory
• www.cisa.gov/known-exploited-vulnerabilities-catalogUS Government Resource