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Vulnerability DatabaseCVE-2021-40656
CVE-2021-40656:
NixOS vulnerability analysis and mitigation
Overview
CVE-2021-40656 affects libsixel versions before 1.10, specifically related to a Buffer Overflow vulnerability in libsixel/src/quant.c:867. The vulnerability was discovered and disclosed in September 2021 (GitHub Issue).
Technical details
The vulnerability is a heap-based buffer overflow that occurs in the error_diffuse function within libsixel/src/quant.c at line 876. The issue manifests when processing certain image parameters, particularly when x=0, y=0, and width=1, leading to an overflow condition that writes to unauthorized heap locations (GitHub Issue).
Impact
When exploited, this vulnerability can lead to heap corruption and potential program crashes. The issue can trigger a 'double free or corruption' error and cause the application to abort execution (GitHub Issue).
Mitigation and workarounds
The vulnerability was fixed in libsixel version 1.10. Users should upgrade to version 1.10 or later to mitigate this issue (Debian Tracker).
Additional resources
Source: This report was generated using AI
Related NixOS vulnerabilities:
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