CVE-2025-8843: 
Linux Debian vulnerability analysis and mitigation

A heap buffer overflow vulnerability has been discovered in NASM (Netwide Assembler) version 2.17rc0, identified as CVE-2025-8843. The vulnerability affects the machonodead_strip function in the outmacho.c file, which is responsible for handling Mach-O output format. The issue was discovered on August 11, 2025, and requires local access to exploit (NVD, Ubuntu).

The vulnerability is caused by insufficient bounds checking when processing Mach-O pragma directives. The issue occurs in the machonodeadstrip function at line 1774, where a string buffer is allocated for only 4 bytes but the program attempts to read beyond its boundaries at offset 0x6020000037b4. The vulnerability has been assigned a CVSS v3.1 base score of 5.3 (Medium) with the vector string CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L ([NASM Bug](https://bugzilla.nasm.us/showbug.cgi?id=3392934)).

The heap buffer overflow vulnerability can lead to memory corruption and potential program crashes. The impact is rated as medium severity, affecting the confidentiality, integrity, and availability of the system with low impact levels. Local access is required to exploit this vulnerability (NVD).

The vulnerability affects NASM version 2.17rc0 and the master branch (commit 888d9ab). As of the initial disclosure, the status is marked as OPEN and requires evaluation across various platforms including Ubuntu distributions from 16.04 LTS to 25.04 (Ubuntu).