BOSH: Improper Certificate Validation
CVE-2026-41859 is a high-severity improper certificate validation vulnerability in BOSH from Cloud Foundry Foundation, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists version 282.1.9 as the first without the flaw, so updating BOSH to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.1% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update BOSH to 282.1.9 or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Cloud Foundry Foundation | BOSH | before 282.1.9 | 282.1.9 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- LocalThe attacker needs local access or must trick a user into running something.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (vmware.com).
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 7.1 | High | CNA (vmware.com) |
| CVSS 3.1 | 7.8 | High | CNA (vmware.com) |
Official description
A network man-in-the-middle between nats-sync and the BOSH director can steal the director credentials (Basic auth header or UAA client secret) and can tamper with the VM list that is written into the NATS authorization file. Stolen credentials grant administrative director access. UsersSync#bosh_api_response_body builds a Net::HTTP client with verify_mode = OpenSSL::SSL::VERIFY_NONE for every director call (/info, /deployments, /deployments/<name>/vms). Affected versions: - BOSH: all versions prior to v282.1.9 (inclusive); fixed in v282.1.9 or later
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Certificate Validation
The product does not validate, or incorrectly validates, a certificate.
How developers prevent this class of flaw
- Certificates should be carefully managed and checked to assure that data are encrypted with the intended owner's public key.
- If certificate pinning is being used, ensure that all relevant properties of the certificate are fully validated before the certificate is pinned, including the hostname.
More Improper Certificate Validation vulnerabilities (CWE-295)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Other references
Other vulnerabilities in BOSH
- 8.8 High severity
- 8.2 High severity
Recent Improper Certificate Validation vulnerabilities
- 8.7 High severity
- 8.1 High severity
- 8.1 High severity
- 8.1 High severity
- 8.2 High severity
- 7.1 High severity
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