CVE-2026-3234
MediumCVSS 4.3Exploitation Probability (EPSS)
Low risk29th percentile - higher than 29% of all known CVEs
Summary
A flaw was found in mod_proxy_cluster: a CRLF injection in the decodeenc() function allows a remote attacker to bypass input validation. By injecting CRLF sequences into the cluster configuration, an attacker can corrupt the response body of INFO endpoint responses. Exploitation requires network access to the MCMP protocol port but no authentication.
Risk Assessment
An unauthenticated attacker with network access could corrupt INFO endpoint responses and potentially affect cluster configuration integrity. This threatens the integrity of the cluster management system.
Recommendation
Update mod_proxy_cluster to a version containing the fix. Restrict network access to the MCMP protocol port to trusted hosts only.
Other vulnerabilities in mod_proxy_cluster
See all- CVE-2024-10306Medium
A vulnerability was found in mod_proxy_cluster where the <Directory> directive is incorrectly used instead of <Location>. The <Directory> directive does not restrict access based on IP address, allowing anyone with host access to send MCMP requests that can add, remove, or update load-balancing nodes.
- CVE-2023-6710Medium
A flaw was found in the mod_proxy_cluster in the Apache server. This issue may allow a malicious user to add a script in the 'alias' parameter in the URL to trigger the stored cross-site scripting (XSS) vulnerability. By adding a script on the alias parameter on the URL, it adds a new virtual host and adds the script to the cluster-manager page.
Original NVD description (English source)
A flaw was found in mod_proxy_cluster. This vulnerability, a Carriage Return Line Feed (CRLF) injection in the decodeenc() function, allows a remote attacker to bypass input validation. By injecting CRLF sequences into the cluster configuration, an attacker can corrupt the response body of INFO endpoint responses. Exploitation requires network access to the MCMP protocol port, but no authentication is needed.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS