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Vulnerability DatabaseCVE-2021-33455

CVE-2021-33455: 
NixOS vulnerability analysis and mitigation

Overview

An issue was discovered in yasm version 1.3.0. There is a NULL pointer dereference vulnerability in the do_directive() function within modules/preprocs/nasm/nasm-pp.c. The vulnerability was reported in May 2021 and affects the YASM assembler software (Debian Tracker, YASM Issue).

Technical details

The vulnerability exists in the do_directive() function located in modules/preprocs/nasm/nasm-pp.c at line 2355. When processing certain malformed input files, the function attempts to dereference a NULL pointer, leading to a segmentation fault. This was confirmed through testing with Address Sanitizer (ASAN) which detected a SEGV (segmentation violation) on an unknown address 0x000000000001 (YASM Issue).

Impact

When exploited, this vulnerability can cause the YASM assembler to crash due to the NULL pointer dereference, resulting in a denial of service condition. The issue affects multiple distributions including Debian's bullseye, bookworm, trixie, and sid releases (Debian Tracker).

Mitigation and workarounds

The vulnerability remains unpatched in YASM 1.3.0. All current versions of the software in various distributions are marked as vulnerable (Debian Tracker).

Additional resources

Source: This report was generated using AI

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