CVE-2024-38475

Published Jul 1, 2024

Last updated 6 days ago

Apache HTTP Server

Overview

AI description

Automated description summarized from trusted sources.

CVE-2024-38475 involves improper output escaping in the `mod_rewrite` module of the Apache HTTP Server, specifically in versions 2.4.59 and earlier. This flaw allows an attacker to map URLs to filesystem locations that the server is permitted to serve but are not intended to be directly accessible. This vulnerability can lead to code execution or source code disclosure. The issue arises when substitutions in the server context use backreferences or variables as the initial segment of the substitution. While the fix might break some existing RewriteRules, the "UnsafePrefixStat" flag can be used to revert to the previous behavior if the substitution is appropriately constrained.

Description: 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.
Source: security@apache.org
NVD status: Analyzed

Risk scores

CVSS 3.1

Type: Secondary
Base score: 9.1
Impact score: 5.2
Exploitability score: 3.9
Vector string: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Severity: CRITICAL

Known exploits

Data from CISA

Vulnerability name: Apache HTTP Server Improper Escaping of Output Vulnerability
Exploit added on: May 1, 2025
Exploit action due: May 22, 2025
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.

Weaknesses

security@apache.org: CWE-116

Hype score is a measure of social media activity compared against trending CVEs from the past 12 months. Max score 100.

Hype score: 1

Configurations

[
  {
    "nodes": [
      {
        "negate": false,
        "cpeMatch": [
          {
            "criteria": "cpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:*",
            "vulnerable": true,
            "matchCriteriaId": "13126636-FD76-4E3E-B949-14A5082DE02A",
            "versionEndExcluding": "2.4.60",
            "versionStartIncluding": "2.4.0"
          }
        ],
        "operator": "OR"
      }
    ]
  },
  {
    "nodes": [
      {
        "negate": false,
        "cpeMatch": [
          {
            "criteria": "cpe:2.3:a:netapp:ontap_9:-:*:*:*:*:*:*:*",
            "vulnerable": true,
            "matchCriteriaId": "AD886814-B4A0-4764-9F08-2060601D8E89"
          }
        ],
        "operator": "OR"
      }
    ]
  }
]

References

Sources include official advisories and independent security research.