Hazard

Is CVE-2021-40438 being exploited?

Ransomware crews are using this

CISA has linked this vulnerability to known ransomware campaigns. Treat any exposed instance as an active incident, not a patching ticket.

Apache HTTP Server-Side Request Forgery (SSRF)

Apache · Apache

CVSS 9 EPSS 100% no public exploit indexed ransomware Fix deadline passed 15 December 2021

What it is

A crafted request uri-path can cause mod_proxy to forward the request to an origin server choosen by the remote user. This issue affects Apache HTTP Server 2.4.48 and earlier.

Why we say that

  • Linked by CISA to known ransomware campaigns
  • EPSS puts exploitation in the next 30 days at 100%
  • CISA's federal remediation deadline (2021-12-15) has passed
  • CVSS 9 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 updates per vendor instructions.

What it costs when this goes wrong

This is where UK enforcement meets the vulnerability record. This vulnerability is used in ransomware campaigns; here is what ransomware has cost UK organisations at the regulator.

All UK cases caused by ransomware →