RoundCube Webmail Deserialization of Untrusted Data Vulnerability

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.

Published 11 Sep 2026Updated 11 Sep 20264 sources
CVSS 9.9 ✓ VERIFIED REFERENCE△ CISA KEV

What happened

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.

Affected versions

Webmail: See original advisory Fixed: See vendor advisory.

Why it matters

This source correlation may provide earlier visibility while structured CVE metadata is still being updated.

Detection & mitigation

  • Review the original advisory and validate affected versions.
  • Apply vendor-provided updates or mitigations when available.

Public PoC references