CVE-2014-3583 in Enterprise Manager
Summary
by MITRE
The handle_headers function in mod_proxy_fcgi.c in the mod_proxy_fcgi module in the Apache HTTP Server 2.4.10 allows remote FastCGI servers to cause a denial of service (buffer over-read and daemon crash) via long response headers.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 07/01/2018
The vulnerability identified as CVE-2014-3583 resides within the mod_proxy_fcgi module of the Apache HTTP Server version 2.4.10, specifically within the handle_headers function in the mod_proxy_fcgi.c source file. This flaw represents a critical buffer over-read condition that can be exploited by remote FastCGI servers to trigger a denial of service attack against the affected Apache daemon. The vulnerability occurs when the module processes response headers from FastCGI applications, creating a scenario where insufficient bounds checking allows malicious input to exceed allocated buffer boundaries.
The technical implementation of this vulnerability stems from inadequate input validation within the FastCGI proxy handling mechanism. When Apache receives response headers from a FastCGI server through the mod_proxy_fcgi module, the handle_headers function fails to properly validate the length of incoming header data before copying it into internal buffers. This oversight creates a condition where a remote FastCGI server can craft specially crafted response headers that exceed the expected buffer size, resulting in memory corruption that manifests as a buffer over-read. The over-read condition causes the Apache daemon to access memory locations beyond the allocated buffer boundaries, ultimately leading to unpredictable behavior and system instability.
The operational impact of CVE-2014-3583 extends beyond simple service disruption, as it can result in complete daemon crashes and system unavailability. When exploited, this vulnerability allows remote attackers to perform denial of service attacks against Apache HTTP servers configured with mod_proxy_fcgi, potentially affecting web applications that rely on FastCGI for dynamic content generation. The attack vector is particularly concerning because it requires no authentication or privileged access, making it accessible to any remote attacker who can establish communication with the vulnerable server. This vulnerability affects organizations running Apache 2.4.10 with mod_proxy_fcgi enabled, potentially compromising web application availability and user access to services.
The vulnerability aligns with CWE-121, which addresses stack-based buffer overflow conditions, and represents a classic example of improper input validation in network protocol handling. From an adversarial perspective, this weakness maps to ATT&CK technique T1499.004 for network denial of service attacks, specifically targeting application layer services. The flaw demonstrates the importance of input sanitization and bounds checking in server-side components that process untrusted data from external sources. Organizations should implement immediate mitigations including upgrading to Apache HTTP Server versions that address this vulnerability, disabling mod_proxy_fcgi if not required, or implementing network-level restrictions to limit access to FastCGI endpoints. The security community has classified this as a high-severity issue due to its remote exploitability and potential for widespread service disruption across web infrastructure relying on Apache with FastCGI support.