Known exploited vulnerability · Apache

CVE-2024-38475: Apache HTTP Server Improper Escaping of Output Vulnerability

criticalCVSS 3.1 9.1Exploited

Improper escaping of output in modrewrite 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.

Published Jul 1, 2024 · Updated Jun 17, 2026

Required action

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

Advisory details

From the National Vulnerability Database. This product uses the NVD API but is not endorsed or certified by the NVD.

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.

References

How this page is made: the data panel comes from the GitHub Advisory Database, CISA’s KEV catalog, the NVD and FIRST EPSS, and updates twice a day. No analysis has been written for this entry yet. Methodology

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