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  3. CVE-2025-49113
Exploited in the wildServers & business softwareWork IT

CVE-2025-49113 Roundcube Webmail: unsafe data loading

In plain words: The program unpacks saved data from outside without checking it is safe. Usually lets an attacker run code on the server.

Confirmed exploited by CISA on · US federal patch deadline Mar 13, 2026

What to do

  1. Install Roundcube's security update for Webmail. If no update exists, follow the vendor's workaround or stop using the product until one ships.
  2. Keep a list of every internet-facing server you run so nothing is forgotten.
  3. Patch anything in this catalog first, ahead of normal patch cycles.
  4. Put admin and file-transfer apps behind a VPN or single sign-on instead of the open internet.

Read Roundcube's advisory ↗

Who is affected

Work IT. Aimed mostly at company systems — you are affected through the companies you use, not your own phone.

What's at risk: Mass data theft and ransomware: a single flaw in a file-transfer or email server has exposed thousands of organisations at once.

The details

Official name
RoundCube Webmail Deserialization of Untrusted Data Vulnerability
Product
Roundcube Webmail
CISA description
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.
Type of flaw
Unsafe data loading (CWE-502)
Confirmed exploited
Feb 20, 2026
US federal patch deadline
Mar 13, 2026

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Answering about CVE-2025-49113 ·

Questions about CVE-2025-49113

Is CVE-2025-49113 being exploited?

Yes. CISA added CVE-2025-49113 to its Known Exploited Vulnerabilities catalog on Feb 20, 2026, which means there is reliable evidence of real-world attacks.

How do I fix CVE-2025-49113?

Install Roundcube's security update for Webmail. If no update exists, follow the vendor's workaround or stop using the product until one ships. Keep a list of every internet-facing server you run so nothing is forgotten.

Am I affected by CVE-2025-49113?

Only if you use Roundcube Webmail. Aimed mostly at company systems — you are affected through the companies you use, not your own phone.

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