Medium File handling

CVE-2026-41009 — Local Blobstore may allow arbitrary reads/deletes

When 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

Published May 27, 2026 · Updated Oct 13, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: vmware

Low

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.

How the score was calculated

EPSS 0.1% (30-day exploitation probability)+0
Technical severity (medium)+3

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation

Not confirmed

Not in CISA KEV — an absence of record, not proof it is unexploited.

EPSS FIRST

0.13%

ahead of 2% of scored CVEs · Oct 14, 2026

Affects

Cloud Foundry Foundation

Bosh and 1 more

CVSS base

5.8

Medium · 2 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation

None

none · proof-of-concept · active

Automatable

can an attacker script the kill-chain steps

Technical impact

Partial

partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

Documented mitigation — www.cloudfoundry.org (NIST National Vulnerability Database)

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

Identify exposed assets running the affected vendor/product/version combinations (Cloud Foundry Foundation Bosh, Cloud Foundry Foundation BOSH Director).
Apply the documented mitigations until a definitive fix is available.
Exploitation requires user interaction: tighten email/web filtering and warn affected users.
Search available logs for exploit probes matching the vulnerability class (file handling), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Vendor	Product	Versions	Status	Source
Cloud Foundry Foundation	Bosh	< 282.1.12	Vulnerable	NIST National Vulnerability Database
Cloud Foundry Foundation	BOSH Director	< 282.1.12	Vulnerable	CVE Program (cve.org) e CISA ADP

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector

Local

Attack complexity

High

Privileges required

High

User interaction

Required

Scope

Changed

Confidentiality

None

Integrity

High

Availability

Low

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

Score	Version	Severity	Expl.	Impact	Scored by
4.3	CVSS 4.0	Medium	—	—	security@vmware.com via NIST National Vulnerability Database
4.3	CVSS 4.0	Medium	—	—	vmware via CVE Program (cve.org) e CISA ADP
5.8	CVSS 3.1	Medium	0.6	4.7	security@vmware.com via NIST National Vulnerability Database
5.8	CVSS 3.1	Medium	—	—	vmware via CVE Program (cve.org) e CISA ADP

CVSS:3.1/AV:L/AC:H/PR:H/UI:R/S:C/C:N/I:H/A:L (score shown at the top: security@vmware.com)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-22 · Path Traversal

Other CVEs with this weakness →

EPSS over time FIRST

Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.13%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

Local/physical vector: focus on endpoint telemetry (EDR) from affected hosts.
Monitor file creation in web directories and paths with traversal sequences (../).

endpoint telemetry (EDR)file integrity (FIM)

Timeline

What happened to this CVE, newest first.

2026
Affected products added · cloud foundry foundation/bosh director
Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
SSVC assessment updated
Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
Record published
Oct 13, 2026
Fix documented
Oct 13, 2026 · NIST National Vulnerability Database
CVSS changed · 5.8
Oct 13, 2026 · NIST National Vulnerability Database
Source status changed · → Analyzed
Oct 13, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 13, 2026 · NIST National Vulnerability Database
CVE published
May 27, 2026 · vmware

Source activity

Repeated readings are counted rather than listed.

1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

1 on the record

www.cloudfoundry.org/blog/cve-2026-41009-local-blobstore-may-allow-arbitrary-reads-deletes
Mitigation, Vendor Advisory, NIST National Vulnerability Database

Elsewhere on this site

Cloud Foundry Foundation
every CVE for this vendor

File handling
same class

CWE-22
other pages naming this weakness

Related CVEs (same products)

Medium CVE-2026-41861 Arbitrary Root File Write via Path Traversal in BOSH agent Aug 6, 2026
High CVE-2026-41010 OS Command Injection in Cloud Foundry Foundation BOSH Director Jun 4, 2026
High CVE-2026-41860 Inadequate Encryption Strength in Cloud Foundry Foundation Bosh Jun 4, 2026
High CVE-2026-41011 OS Command Injection in Cloud Foundry Foundation Bosh Jun 4, 2026
High CVE-2026-41859 Improper Certificate Validation in Cloud Foundry Foundation Bosh Jun 4, 2026
Medium CVE-2026-41704 Compromised VM can make arbitrary blobstore deletes May 27, 2026

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-41009 is "Local Blobstore may allow arbitrary reads/deletes", rated Medium. It affects Bosh (Cloud Foundry Foundation); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 5.8 describes technical severity. EPSS 0.13% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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