CVE-2024-38475

Improper escaping of output in mod_rewrite in Apache HTTP Server 2.4.59 and earlier allows an attacker to map URLs to filesystem locations that are permitted to be served by the server but are not intentionally/directly reachable by any URL, resulting in code execution or source code disclosure. Substitutions in server context that use a backreferences or variables as the first segment of the substitution are affected. Some unsafe RewiteRules will be broken by this change and the rewrite flag "UnsafePrefixStat" can be used to opt back in once ensuring the substitution is appropriately constrained.

Score: CVSS 3.1 9.1 Critical
Status: Analyzed - security@apache.org
Published: 2024-07-01
Last modified: 2025-11-03
Known exploited (CISA KEV): since 2025-05-01, action due 2025-05-22: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Weaknesses: CWE-116

Affected products

References

https://httpd.apache.org/security/vulnerabilities_24.html
https://security.netapp.com/advisory/ntap-20240712-0001/
http://www.openwall.com/lists/oss-security/2024/07/01/8
https://github.com/apache/httpd/commit/9a6157d1e2f7ab15963020381054b48782bc18cf
https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2024-0018
https://www.blackhat.com/us-24/briefings/schedule/index.html#confusion-attacks-exploiting-hidden-semantic-ambiguity-in-…
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2024-38475