CVE-2026-41991 (GCVE-0-2026-41991)

Vulnerability from cvelistv5 – Published: 2026-06-29 10:15 – Updated: 2026-06-29 13:31 X_Open Source
VLAI
Title
Predictable Temporary File in GNU gzip
Summary
GNU gzip contains a vulnerability in the gzexe utility related to insecure temporary file handling. When the mktemp utility is not available in the user’s PATH, gzexe falls back to constructing a temporary file path based solely on the process ID (PID). This predictable filename is created without exclusive access or existence checks. A local attacker can pre‑create the predicted temporary file path as a symbolic link pointing to an arbitrary file writable by the victim. When gzexe runs, it follows the symlink and overwrites the target file, resulting in a time‑of‑check to time‑of‑use (TOCTOU) condition that allows arbitrary file overwrite. This issue has been fixed in the commit 4e6f8b24ab823146ab8776f0b7fe486ab34d4269
Severity
2 (Low)
CVSS:4.0/AV:L/AC:H/AT:P/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-29 13:31 UTC
CWE
  • CWE-377 - Insecure Temporary File
Assigner
CERT-PL CNA under the ENISA root
CNA scorecard B 81/100 over 256 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
GNU gzip Affected: 0 , ≤ 1.14 (semver)
guessed Create a notification for this product.
Credits
Michał Majchrowicz (AFINE) Marcin Wyczechowski (AFINE)
Show details on NVD website
To clipboard 

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  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

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    Related by attack behaviour

    Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.