Path Traversal in activestorage (CVE-2026-33195)
Summary
Path traversal in activestorage (CVE-2026-33195). Successful exploitation can lead to full system takeover. Mitigation: upgrade to 7.2.3.1 or later.
Original description
The description as published by the source.
Impact
Active Storage's DiskService#path_for does not validate that the resolved filesystem path remains within the storage root directory. If a blob key containing path traversal sequences (e.g. ../) is used, it could allow reading, writing, or deleting arbitrary files on the server. Blob keys are expected to be trusted strings, but some applications could be passing user input as keys and would be affected.
Releases
The fixed releases are available at the normal locations.
Credit
This issue was responsibly reported by Hackerone researcher ksw9722.
Source: GitHub Security Advisories (Global) 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-2026-33195 has been found in activestorage.
Successful exploitation can lead to full system takeover. CVSS score: 9.8/10.
What to do: upgrade activestorage to 7.2.3.1 or later.
If unsure, ask your IT team or search "activestorage CVE-2026-33195" on the vendor's site.
CVE-2026-33195 (activestorage) — CWE-22 / CVSS v3 9.8
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Patched: 7.2.3.1 — apply immediately
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.
Path traversal (CWE-22) exists in activestorage.
Check the vendor advisory for the affected versions of activestorage.
Severity: Critical (CVSS 9.8/10). Successful exploitation can lead to full system takeover.
Update to 7.2.3.1.
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 'activestorage' . 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 'activestorage' . | 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
activestorageを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade activestorage to 7.2.3.1ステージング環境で 7.2.3.1 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
3Post-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。
Affected packages
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2026-33195 rails
- Ubuntu UBUNTU-CVE-2026-33195 rails
References
- advisory nvd.nist.gov
- package github.com
- patch security-advisories@github.com
- patch security-advisories@github.com
- patch security-advisories@github.com
- patch security-advisories@github.com
- web security-advisories@github.com
- web security-advisories@github.com
- web security-advisories@github.com
- web github.com
- web github.com
- web access.redhat.com
- web bugzilla.redhat.com
- web security.access.redhat.com