CVE-2021-40438
mod_proxy SSRF
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Listed in CISA KEV
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
The Apache HTTP Server's mod_proxy module is affected. A remote attacker can craft a request path that causes the server to forward the request to a destination of the attacker's choosing, which can expose internal systems to unauthorized requests.
Summarized by anthropic/claude-haiku-5.5. Verify details against the original sources.
Read the original description
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.
Timeline
- CVE published
- Added to CISA KEV
CISA has evidence of exploitation in the wild
- CISA remediation deadline
Due date for US federal agencies to patch
- Record last updated
- EPSS reached 10%
FIRST estimates at least a 10% chance of exploitation in the next 30 days
Affected versions
- Apache Software Foundation Apache HTTP Server
From Apache HTTP Server 2.4 · through 2.4.48
References 19
httpd.apache.org
lists.fedoraproject.org
lists.apache.org
- thread.html/r82838efc5fa6fc4c73986399c9b71573589f78b31846aff5bd9b1697@<users.httpd.apache.org>
- thread.html/r82c077663f9759c7df5a6656f925b3ee4f55fcd33c889ba7cd687029@<users.httpd.apache.org>
- thread.html/r3925e167d5eb1c75def3750c155d753064e1d34a143028bb32910432@<users.httpd.apache.org>
- thread.html/r61fdbfc26ab170f4e6492ef3bd5197c20b862ce156e9d5a54d4b899c@<users.httpd.apache.org>
- thread.html/r2eb200ac1340f69aa22af61ab34780c531d110437910cb9c0ece3b37@<bugs.httpd.apache.org>
- thread.html/r210807d0bb55f4aa6fbe1512be6bcc4dacd64e84940429fba329967a@<users.httpd.apache.org>
- thread.html/rf6954e60b1c8e480678ce3d02f61b8a788997785652e9557a3265c00@<users.httpd.apache.org>