CVE-2026-89091

high

Description

A flaw was found in ansible-core. When installing a collection with `ansible-galaxy collection install`, the archive extractor validates member paths using lexical path normalisation (os.path.abspath) instead of resolving symbolic links (os.path.realpath), and it performs no containment check on symlink-typed directory members before creating them. A crafted collection tarball can chain symlink directory entries so that a subsequent file member is written outside the intended destination directory. This allows an attacker who can get a victim to install a malicious collection to overwrite arbitrary files with the privileges of the user running ansible-galaxy, leading to code execution on the control node. This is a bypass of the fix for CVE-2020-10691.

References

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-95346

https://bugzilla.redhat.com/show_bug.cgi?id=2531646

https://access.redhat.com/security/cve/CVE-2026-89091

Details

Source: Mitre, NVD

Published: 2026-10-08

Updated: 2026-10-09

Risk Information

CVSS v2

Base Score: 10

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C

Severity: Critical

CVSS v3

Base Score: 8.8

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Severity: High

EPSS

EPSS: 0.0048