CVE-2026-66485 PUBLISHED

Uncontrolled Memory Allocation in GNU cpio

Assigner: CERT-PL
Reserved: 27.07.2026 Published: 10.08.2026 Updated: 10.08.2026

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

Metrics

CVSS Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
CVSS Score: 4.6

Product Status

Vendor GNU
Product cpio
Versions Default: unaffected
  • affected from 0 to 2.15 (incl.)

Credits

  • Michał Majchrowicz (AFINE Team) finder
  • Marcin Wyczechowski (AFINE Team) finder

References

Problem Types

  • CWE-789 Memory allocation with excessive size value CWE