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.
A remote attacker, with a low-privilege account, can achieve full data confidentiality loss, arbitrary modification of data, complete denial of service or system unavailability. Federal agencies are required to remediate by 2026-03-13 under CISA BOD 22-01.
This is a Deserialization of Untrusted Data (CWE-502) vulnerability in Roundcube Webmail. Exploitation requires remote network access, low attack complexity, a low-privilege authenticated account, and no user interaction required.
Probably yes if any of these apply:
Active exploitation documented in the wild. Threat-research write-up: https://www.vicarius.io/vsociety/posts/cve-2025-49113-roundcube-mitigation-script
Manual remediation steps
Apply the Vendor Patch
This vulnerability is in the CISA Known Exploited Vulnerabilities catalog — apply the vendor's security update as soon as possible.
CISA 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.
References
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References