CVE-2026-41009
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedWhen the director sends a long-running request (e.g. compile_package), the agent's reply JSON is consumed by AgentClient. inject_compile_log (line 332-339) reads response['value']['result']['compile_log_id'] and format_exception (line 318-325) reads exception['blobstore_id']; both pass the agent-supplied string unmodified to download_and_delete_blob(blob_id) (line 344-349), which calls @resource_manager.get_resource(blob_id) and, in an ensure block, @resource_manager.delete_resource(blob_id). Api::ResourceManager forwards the id straight to blobstore.get(id) / blobstore.delete(id). When the director is configured with the local blobstore provider, Blobstore::LocalClient#object_file_path(oid) is File.join(@blobstore_path, oid) (local_client.rb:54-56) with no normalisation, so oid = "../../jobs/director/config/director.yml" resolves outside the blobstore root. Affected versions: BOSH Director: All versions prior to v282.1.12
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceBOSH Director contains a path traversal vulnerability in its local blobstore client. The agent-supplied blob_id is passed directly to File.join(@blobstore_path, oid) without validation, allowing an attacker to use paths like '../../jobs/director/config/director.yml' to access arbitrary files on the director filesystem.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data< 282.1.12CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Local
- Complexity
- High
- Privileges
- High
- User interaction
- Required
- Scope
- Changed
- Confidentiality
- None
- Integrity
- High
- Availability
- Low
CVSS:3.1/AV:L/AC:H/PR:H/UI:R/S:C/C:N/I:H/A:L
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
-
Identify BOSH Director installation and versionCheck the BOSH Director version by running 'bosh --version' or inspecting the deployment manifest under '/jobs/director/spec' if deployed via BOSH. Alternatively, query the BOSH API at '/info' endpoint which returns the version in the response.Affected if The installed version is less than 282.1.12
-
Confirm local blobstore driver is in useInspect the BOSH Director configuration file typically located at '/jobs/director/config/director.yml' or the manifest used to deploy the Director. Look for the 'blobstore' section and verify the 'provider' field is set to 'local'.Affected if The blobstore provider is 'local' (this is required for the path traversal to be exploitable)
-
Verify agent network access to DirectorReview network ACLs, security groups, or firewall rules controlling access to the BOSH Director API port (usually 25555). Check if untrusted agents or arbitrary network sources can reach the Director's blobstore endpoint.Affected if Agents or untrusted network sources have unrestricted access to the Director (enables the attack vector)
Your environment is affected if BOSH Director version is below 282.1.12, the blobstore is configured to use the local provider, and agents have network access to submit blobstore requests.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scoped282.1.12
Upgrade BOSH Director to v282.1.12 or later which includes path normalization in the blobstore client. As a compensating control, restrict agent network access to trusted sources only.
BOSH Director v282.1.12
- Determine the current BOSH Director version using 'bosh env' or by checking the deployed releases
- Review the BOSH release notes and migration guide for version 282.1.12
- Upgrade the BOSH Director to version 282.1.12 or later by updating the BOSH release
- Verify the upgrade was successful by confirming the director version and testing that the local blobstore properly normalizes paths
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation3.0 h
- Implementation6.0 h
- Testing6.0 h
- Review / QA3.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $4,992.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-41009 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2026-41009 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.
A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.
- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
- No spam, self-promotion, credentials, or personal data