Vulnerability in ansible-core (CVE-2026-89091)
Summary
Vulnerability in ansible-core (CVE-2026-89091). Successful exploitation can lead to full system takeover.
Original description
The description as published by the source.
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.
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-89091 has been found in ansible-core.
Successful exploitation can lead to full system takeover. CVSS score: 8.8/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "ansible-core CVE-2026-89091" on the vendor's site.
CVE-2026-89091 (ansible-core) — CWE-59 / CVSS v3 8.8
Attack vector: remote (network-reachable) / unauthenticated
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-59) exists in ansible-core.
Check the vendor advisory for the affected versions of ansible-core.
Severity: High (CVSS 8.8/10). Successful exploitation can lead to full system takeover.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'ansible-core' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'ansible-core' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
ansible-coreを grep し、稼働しているサービス・バージョンを把握する。 -
2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
References
- web secalert@redhat.com
- web secalert@redhat.com
- web nvd.nist.gov
- web github.com