CVE-2026-66485
MediumCVSS 4.6Exploitation Probability (EPSS)
Low risk3th percentile - higher than 3% of all known CVEs
Summary
GNU cpio is vulnerable to an uncontrolled memory allocation in the make_path function at src/makepath.c. The function uses alloca to allocate stack memory based on the length of argpath, which is derived from an archive-controlled pathname during extraction. A malicious cpio archive containing a sufficiently long nested pathname causes an unbounded stack allocation, resulting in a stack overflow and crash of the cpio process.
Risk Assessment
An attacker can supply a crafted archive that, when extracted by a victim, can cause the cpio process to crash, leading to denial of service.
Recommendation
Update GNU cpio to a version containing commit 3cd514031371d8aeeaf2048aa10103e02831aaa9 or later. Avoid extracting archives from untrusted sources.
Other vulnerabilities in GNU cpio
See all- CVE-2026-66486Medium
GNU cpio is vulnerable to improper encoding or escaping of output in its archive member listing functionality. When listing archive members via cpio -it, member names are printed directly to output without quoting or escaping. An attacker can craft a cpio archive containing member names with embedded newline characters or ANSI escape sequences, causing forged listing entries or terminal control sequence injection when the listing is displayed.
- CVE-2026-66484Medium
GNU cpio contains a Path Traversal vulnerability in its tar archive extraction functionality. When extracting a tar archive in copy-in mode with the --no-absolute-filenames option, the extracted file name is normalized but the tar hard-link target is passed to the link_to_name function without equivalent sanitization before calling link function. A tar archive provided by an attacker, containing a hard-link entry whose linkname is set to an absolute path outside the extraction directory, can cause cpio to create a hard link to an existing file outside the intended extraction directory, breaking the expected guarantee of --no-absolute-filenames and allowing archive-controlled linkage to external files.
Original NVD description (English source)
GNU cpio is vulnerable to an uncontrolled memory allocation in the make_path function at src/makepath.c. The function uses alloca to allocate stack memory based on the length of argpath, which is derived from an archive-controlled pathname during extraction. A malicious cpio archive containing a sufficiently long nested pathname causes an unbounded stack allocation, resulting in a stack overflow and crash of the cpio process. An attacker who can supply a crafted cpio archive to a victim who extracts it can cause a denial of service. This issue has been fixed in commit 3cd514031371d8aeeaf2048aa10103e02831aaa9
Vulnerability data from NVD (NIST) · CISA KEV · EPSS