Hazard

Is CVE-2024-42009 being exploited?

Weaponised and widely attempted

Reliable public exploit code exists, or mass exploitation attempts are probable. Patch inside days, not weeks.

RoundCube Webmail Cross-Site Scripting Vulnerability

Roundcube · Webmail

CVSS 9.3 EPSS 80% no public exploit indexed Fix deadline passed 30 June 2025

What it is

RoundCube Webmail contains a cross-site scripting vulnerability. This vulnerability could allow 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.

Why we say that

  • EPSS puts exploitation in the next 30 days at 80%
  • CISA's federal remediation deadline (2025-06-30) has passed
  • CVSS 9.3 critical
  • Listed in the CISA Known Exploited Vulnerabilities catalogue

Every line above comes from a named public source. Where the evidence is thin, we say so rather than inventing confidence — see methodology.

What to do

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

What it costs when this goes wrong

This is where UK enforcement meets the vulnerability record. Where an unfixed vulnerability leads to a breach, the ICO treats it as a security failure under UK GDPR. Recent cases:

All UK cases caused by unpatched software →