CVE-2012-6617 in FFmpeg
Summary
by MITRE
The prepare_sdp_description function in ffserver.c in FFmpeg before 1.0.2 allows remote attackers to cause a denial of service (crash) via vectors related to the rtp format.
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Analysis
by VulDB Data Team • 08/25/2025
The vulnerability identified as CVE-2012-6617 represents a critical denial of service flaw within the FFmpeg media processing library, specifically affecting versions prior to 1.0.2. This issue resides in the prepare_sdp_description function located within the ffserver.c source file, which serves as the server component responsible for handling real-time streaming protocols. The flaw manifests when the system processes specific malformed input data related to the rtp format, creating a condition where remote attackers can deliberately trigger system crashes without requiring any authentication or privileged access. This vulnerability directly impacts the stability and availability of media streaming services that rely on FFmpeg for real-time protocol handling, potentially affecting content delivery networks, streaming servers, and media processing applications that utilize this library.
The technical nature of this vulnerability stems from insufficient input validation within the SDP (Session Description Protocol) processing logic. When the prepare_sdp_description function encounters malformed or unexpected rtp format data, it fails to properly handle the edge cases during memory allocation or buffer processing, leading to memory corruption and subsequent system termination. The flaw operates at the protocol parsing layer where the server attempts to construct session descriptions for real-time streaming, making it particularly dangerous as it can be exploited through normal network traffic without requiring special privileges. This type of vulnerability aligns with CWE-121, which describes heap-based buffer overflow conditions, and represents a classic example of improper input validation leading to memory safety issues. The attack vector is particularly concerning as it can be executed remotely over the network, making it a significant threat to streaming services and media servers.
The operational impact of CVE-2012-6617 extends beyond simple service disruption, as it can lead to complete system crashes and availability interruptions for streaming services. Organizations relying on FFmpeg-based streaming solutions face potential business disruption when this vulnerability is exploited, particularly in environments where continuous media availability is critical. The vulnerability affects the broader media processing ecosystem, as FFmpeg is widely used across various applications including content delivery networks, video conferencing systems, and streaming platforms. Attackers can leverage this flaw to repeatedly crash streaming servers, leading to service degradation or complete outages that can result in significant financial losses and reputational damage. This vulnerability also demonstrates the importance of proper input sanitization in protocol handling components, as it can be exploited by attackers to gain unauthorized service disruption without requiring complex exploitation techniques.
Mitigation strategies for this vulnerability primarily focus on immediate software updates and patches to FFmpeg versions 1.0.2 and later, which contain the necessary fixes for the input validation issues in the prepare_sdp_description function. System administrators should prioritize updating their FFmpeg installations across all streaming servers and media processing systems to eliminate the risk of exploitation. Additional defensive measures include implementing network-level filtering to restrict access to streaming ports and protocols, deploying intrusion detection systems to monitor for suspicious SDP-related traffic patterns, and establishing robust monitoring protocols to detect service disruptions. Organizations should also consider implementing application-level firewalls or proxy solutions that can validate and sanitize SDP data before it reaches the vulnerable FFmpeg components. The remediation process should follow standard security practices including vulnerability assessment, patch testing in staging environments, and comprehensive deployment across all affected systems. This vulnerability highlights the necessity of continuous security maintenance and the importance of staying current with security patches in media processing infrastructure.