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Vulnerability DatabaseCVE-2020-21598

CVE-2020-21598: 
NixOS vulnerability analysis and mitigation

Overview

libde265 v1.0.4 contains a heap buffer overflow vulnerability (CVE-2020-21598) in the ffhevcputunweightedpred8sse function. The vulnerability affects the open-source implementation of the H.265 video codec and can be exploited through a specially crafted file (NVD, Debian Advisory).

Technical details

The vulnerability is classified as a heap-based buffer overflow with a CVSS v3.1 Base Score of 8.8 (HIGH) and vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H. The issue specifically occurs in the ffhevcputunweightedpred8sse function when processing crafted video files (NVD).

Impact

If successfully exploited, this vulnerability could lead to denial of service (DoS), memory corruption, or potentially arbitrary code execution when processing malformed media files. The high CVSS score indicates significant potential impact on system confidentiality, integrity, and availability (Debian Advisory).

Mitigation and workarounds

The vulnerability has been patched in multiple distributions. Debian has released fixes in version 1.0.11-0+deb11u1 for the stable distribution (bullseye) and version 1.0.3-1+deb10u2 for Debian 10 buster. Users are strongly recommended to upgrade their libde265 packages to the latest available versions (Debian LTS, Debian Advisory).

Additional resources

Source: This report was generated using AI

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