CVE-2026-89091

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.