CVE-2022-43240 is a heap-buffer-overflow vulnerability identified in libde265 version 1.0.8, specifically within the function ff_hevc_put_hevc_qpel_h_2_v_1_sse located in the sse-motion.cc source file. Libde265 is an open-source HEVC (High Efficiency Video Coding) decoder library used to decode H.265 video streams. The vulnerability arises due to improper bounds checking when processing certain crafted video files, leading to a heap buffer overflow condition. This flaw can be triggered by an attacker supplying a maliciously crafted HEVC video file that exploits the buffer overflow during the motion compensation phase of video decoding. The consequence of this vulnerability is a Denial of Service (DoS) attack, where the target application or system crashes or becomes unresponsive due to memory corruption. The CVSS v3.1 base score is 6.5 (medium severity), reflecting that the attack vector is network-based (AV:N), requires no privileges (PR:N), but does require user interaction (UI:R), and impacts availability (A:H) without affecting confidentiality or integrity. No known exploits are currently reported in the wild, and no patches or vendor-specific mitigations are listed, indicating that users of libde265 should be vigilant and monitor for updates. The vulnerability is classified under CWE-787 (Out-of-bounds Write), a common memory safety issue that can lead to crashes or potentially more severe exploitation if combined with other vulnerabilities.

For European organizations, the primary impact of CVE-2022-43240 is the potential for service disruption through Denial of Service attacks when processing malicious HEVC video files. Organizations that rely on libde265 for video decoding in media players, streaming services, video conferencing tools, or any multimedia processing pipelines are at risk. This can affect media companies, broadcasters, telecommunications providers, and enterprises using video communication platforms. The DoS could lead to downtime, degraded user experience, or interruption of critical video services. Although this vulnerability does not directly compromise confidentiality or integrity, the availability impact can disrupt business operations and customer trust. Additionally, if libde265 is embedded in security-sensitive environments (e.g., video surveillance systems), the DoS could impair security monitoring capabilities. Given the widespread use of HEVC video formats in Europe for broadcasting and streaming, the risk is non-negligible, especially in sectors with high video content consumption or production.

To mitigate CVE-2022-43240, European organizations should: 1) Identify all systems and applications using libde265, particularly version 1.0.8 or earlier. 2) Monitor official libde265 repositories and security advisories for patches or updated versions that address this vulnerability and apply them promptly once available. 3) Implement input validation and filtering to restrict or sanitize untrusted HEVC video files before decoding, especially from external or user-generated sources. 4) Employ sandboxing or containerization for applications that decode video streams to limit the impact of potential crashes. 5) Use runtime memory protection mechanisms such as Address Space Layout Randomization (ASLR) and Data Execution Prevention (DEP) to reduce exploitation risk. 6) Incorporate robust error handling in video processing workflows to gracefully handle decoding failures without service interruption. 7) Educate users and administrators about the risks of opening untrusted video files and enforce policies to avoid processing suspicious media content. These targeted steps go beyond generic advice by focusing on the specific nature of the vulnerability and the typical deployment contexts of libde265.