Path Traversal in Apache (CVE-2026-82427)
Summary
Path traversal in Apache (CVE-2026-82427). Successful exploitation can lead to full system takeover. Exploitable via topology.blobstore.map.
Original description
The description as published by the source.
Description
A topology's topology.blobstore.map lets the submitter choose a local name for each blob that the
supervisor localises. That name was used to build a path under the topology's working directory without
normalisation, in both AsyncLocalizer and Container.createBlobstoreLinks, and the symlink helper
force-deletes whatever already exists at the target before creating the link.
A submitter could therefore use ../ segments to direct that delete-and-symlink operation at an arbitrary
path, as the supervisor user, on every node the topology is scheduled onto. The consequences include
recursive deletion of supervisor-owned content and planting a symlink that causes a subsequent worker
launch to execute attacker-chosen code as another tenant's operating-system user, which defeats the
isolation that supervisor.run.worker.as.user is intended to provide.
Mitigation
Upgrade to 3.1.0, where the resolved target must lie inside the expected root at both call sites.
Users who cannot upgrade immediately should restrict topology submission to trusted principals, and may
reject submissions whose topology.blobstore.map entries contain path separators or .. segments before
they reach Nimbus.
Credit
The ASF -- found using Claude agents to study the security of open-source projects, validated and reported by Apache Storm.
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-2026-82427 has been found in Apache.
Attackers can target a specific entry point like topology.blobstore.map over the network to misuse the product.
Successful exploitation can lead to full system takeover. CVSS score: 7.8/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Apache CVE-2026-82427" on the vendor's site.
CVE-2026-82427 (Apache) — CWE-22 / CVSS v3 7.8
Attack vector: local / no user interaction
Attack surface: topology.blobstore.map / AsyncLocalizer / Container.createBlobstoreLinks / supervisor.run.worker.as.user
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 Apache. Attackers reach the vulnerable code path via topology.blobstore.map.
Check the vendor advisory for the affected versions of Apache. Attack surface: topology.blobstore.map / AsyncLocalizer / Container.createBlobstoreLinks / supervisor.run.worker.as.user.
Severity: High (CVSS 7.8/10). 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 'Apache' . 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 'Apache' . | 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
Apache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 lists.apache.org
- web openwall.com
- web nvd.nist.gov
- web github.com