Apache HTTP Server 2.4.x SSRF via mod_proxy+mod_headers (before 2.4.64)
CVE-2024-43204 Published on July 10, 2025
Apache HTTP Server: SSRF with mod_headers setting Content-Type header
SSRF in Apache HTTP Server with mod_proxy loaded allows an attacker to send outbound proxy requests to a URL controlled by the attacker. Requires an unlikely configuration where mod_headers is configured to modify the Content-Type request or response header with a value provided in the HTTP request.
Users are recommended to upgrade to version 2.4.64 which fixes this issue.
Vulnerability Analysis
CVE-2024-43204 is exploitable with network access, and does not require authorization privileges or user interaction. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have no impact on confidentiality, a high impact on integrity, and no impact on availability.
Timeline
reported
Weakness Type
What is a SSRF Vulnerability?
The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination. By providing URLs to unexpected hosts or ports, attackers can make it appear that the server is sending the request, possibly bypassing access controls such as firewalls that prevent the attackers from accessing the URLs directly. The server can be used as a proxy to conduct port scanning of hosts in internal networks, use other URLs such as that can access documents on the system (using file://), or use other protocols such as gopher:// or tftp://, which may provide greater control over the contents of requests.
CVE-2024-43204 has been classified to as a SSRF vulnerability or weakness.
Products Associated with CVE-2024-43204
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Affected Versions
Apache Software Foundation Apache HTTP Server:- Version 2.4.0, <= 2.4.63 is affected.
Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.