CVE-2019-7733 in Live555
Summary
by MITRE
In Live555 0.95, there is a buffer overflow via a large integer in a Content-Length HTTP header because handleRequestBytes has an unrestricted memmove.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 07/09/2023
The vulnerability identified as CVE-2019-7733 affects Live555 version 095, a widely used multimedia streaming library that implements various network protocols including RTSP and HTTP. This flaw manifests as a buffer overflow condition that occurs when processing HTTP requests containing unusually large integer values in the Content-Length header field. The vulnerability stems from inadequate input validation within the library's HTTP request handling mechanism, specifically in the handleRequestBytes function which performs an unrestricted memmove operation without proper bounds checking.
The technical root cause of this vulnerability lies in the improper handling of user-supplied data within the HTTP parsing logic. When a malicious actor sends an HTTP request with an oversized Content-Length value, the library fails to validate the magnitude of this integer before attempting to copy data using memmove. This unrestricted memory operation allows for arbitrary memory overwrite conditions that can be exploited to execute arbitrary code or cause denial of service. The vulnerability is classified as a classic buffer overflow issue that directly maps to CWE-121, which describes stack-based buffer overflow conditions, though in this case the overflow occurs in heap memory due to the memmove implementation.
The operational impact of CVE-2019-7733 extends across numerous applications and services that depend on Live555 for multimedia streaming capabilities. Systems utilizing this library for RTSP streaming, HTTP-based content delivery, or any network protocol handling that processes HTTP headers are potentially vulnerable to exploitation. Attackers could leverage this vulnerability to remotely execute code on affected systems, leading to complete system compromise, or to cause service disruption through controlled crashes. The vulnerability is particularly concerning because Live555 is integrated into many commercial products including video surveillance systems, streaming media servers, and networked multimedia applications, creating a wide attack surface.
Mitigation strategies for this vulnerability require immediate patching of affected Live555 versions to the latest available release that contains the fix for unrestricted memmove operations. Organizations should implement network monitoring to detect and block malformed HTTP requests containing suspicious Content-Length values, particularly those exceeding reasonable thresholds. Input validation controls should be enhanced at the application level to sanitize HTTP headers before they reach the Live555 library processing layer. Security teams should consider implementing intrusion detection systems that can identify patterns associated with exploitation attempts targeting this specific vulnerability. The ATT&CK framework categorizes this type of vulnerability under T1059 for command and control communications and T1203 for exploitation for execution, highlighting the potential for remote code execution and privilege escalation that makes this vulnerability particularly dangerous in enterprise environments.