CVE-2026-41991: GNU gzip contains a vulnerability in the gzexe utility related to insecure temporary file handling

Q: How do I fix CVE-2026-41991?

gzip: upgrade to newer than 1.14. Exact commands for each OS are on this page.

Q: Is CVE-2026-41991 being exploited?

CVE-2026-41991 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2026-41991 affect?

CVE-2026-41991 affects gzip. Severity is medium (CVSS 4.7). 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 proc

Q: How urgent is CVE-2026-41991?

Priority 17/100. No elevated risk signals yet.

Routine

MEDIUM 4.7UPGRADE

CVE-2026-41991 is a medium-severity flaw (CVSS 4.7) affecting gzip. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

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 fil

Why this priority

No elevated risk signals yet

A fixed release or distro patch exists.

Risk facts

CVSS score	4.7 (Medium)
Attack vector	Local
Attack complexity	High
Privileges needed	Low
User interaction	None
EPSS exploit chance	0.1% (top 98%)
CISA exploited list	No
Weakness	CWE-377
Published	2026-06-29
Last modified	2026-10-25

Publisher (CNA): CERT.PL · Vendor: gnu

Last updated 2026-10-25 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-06-29 12:16 UTCPublished CVE record published
2026-10-25 21:10 UTCUpdated Record last modified

gnu gzip UPGRADE

Affected: <= 1.14

Fixed in: newer than 1.14

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy gzip || rpm -q gzip || gzip --version

2. UPGRADE to newer than 1.14 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade gzip

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade gzip

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

Advisories and coverage

Official advisories

CERT Polska: Vulnerabilities in gzip software 2026-06-29

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-41991?

gzip: upgrade to newer than 1.14. Exact commands for each OS are on this page.

Is CVE-2026-41991 being exploited?

CVE-2026-41991 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2026-41991 affect?

CVE-2026-41991 affects gzip. Severity is medium (CVSS 4.7). 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 proc

How urgent is CVE-2026-41991?

Priority 17/100. No elevated risk signals yet.

Related CVEs

CVE-2026-41992 HIGH 7.5 UPGRADE GNU gzip contains a global buffer overflow vulnerability in the LZH decompression logic caused by improper reu

References

← Back to latest CVEs