CVE-2026-41992
HighCVSS 7.5Exploitation Probability (EPSS)
Low risk49th percentile - higher than 49% of all known CVEs
Summary
GNU gzip contains a global buffer overflow vulnerability in the LZH decompression logic caused by improper reuse of shared global state between different decompression formats within a single execution. By decompressing a specially crafted LZW file followed by a specially crafted LZH file in a single gzip -d command, an attacker can poison the shared global state and trigger an out-of-bounds read in the LZH decoder.
Risk Assessment
An attacker could cause a program crash or potentially execute arbitrary code, leading to system integrity compromise or denial of service.
Recommendation
Update GNU gzip to a version containing the fixes (commits 63dbf6b3b9e6e781df1a6a64e609b10e23969681 and e7378c2d421be6a286922374425680bbe9ad8b7d).
Other vulnerabilities in GNU gzip
See all- CVE-2022-1271High
An arbitrary file write vulnerability in GNU gzip's zgrep utility allows an attacker to overwrite arbitrary files. When zgrep processes a crafted file name with multiple newlines, it can write selected content to any file. This is due to insufficient validation of filenames.
- CVE-2026-41991Medium
GNU gzip has a vulnerability in the gzexe utility related to insecure temporary file handling. When mktemp is not available in the user's PATH, gzexe creates a temporary file with a predictable name based solely on the PID, without exclusive access or existence checks. A local attacker can pre-create this path as a symlink to an arbitrary writable file, causing a TOCTOU condition that allows arbitrary file overwrite.
Original NVD description (English source)
GNU gzip contains a global buffer overflow vulnerability in the LZH decompression logic caused by improper reuse of shared global state between different decompression formats within a single execution. GNU gzip maintains a global array that is shared across the LZ77, LZW, and LZH decompression routines and is not reinitialized between files processed in the same invocation. By decompressing a specially crafted LZW file followed by a specially crafted LZH file in a single gzip -d command, an attacker can poison the shared global state and subsequently trigger an out‑of‑bounds read in the LZH decoder. The LZH decompression logic follows stale values left in the shared array, causing reads past the end of the allocated global buffer. This issue has been fixed in commits 63dbf6b3b9e6e781df1a6a64e609b10e23969681 and e7378c2d421be6a286922374425680bbe9ad8b7d.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS