Is CVE-2026-47831 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-47831 being exploited in the wild.

How severe is CVE-2026-47831?

High severity, with a CVSS score of 7.5, published 9 July 2026.

Which products and versions are affected?

Cloud Foundry Foundation bosh-windows-stemcell-builder prior to v2019.98.

Is there a fix for CVE-2026-47831?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2026-47831 attacked?

It is attacked from the adjacent network, in a software library.

Am I affected by CVE-2026-47831?

Check whether you run Cloud Foundry Foundation Bosh-Windows-Stemcell-Builder. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-47831: Cloud Foundry bosh-windows-stemcell-builder weak RNG in GenerateRandomPassword

CVE-2026-47831 · Severity: high · CVSS 7.5 · Published 2026-07-09

A security flaw in the tool used to build Windows base images for Cloud Foundry environments allows for the creation of weak administrative passwords. Because these passwords are generated using a predictable method, an attacker on the same network could potentially guess the credentials and gain full remote access to the system via SSH. This could lead to unauthorized access to sensitive data or the disruption of cloud operations.

Vendors: Cloud Foundry Foundation.

Quick answers

Is CVE-2026-47831 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-47831 being exploited in the wild.
How severe is CVE-2026-47831?: High severity, with a CVSS score of 7.5, published 9 July 2026.
Which products and versions are affected?: Cloud Foundry Foundation bosh-windows-stemcell-builder prior to v2019.98.
Is there a fix for CVE-2026-47831?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-47831 attacked?: It is attacked from the adjacent network, in a software library.
Am I affected by CVE-2026-47831?: Check whether you run Cloud Foundry Foundation Bosh-Windows-Stemcell-Builder. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

The vulnerability stems from the use of a cryptographically weak random number generator (RNG) within the GenerateRandomPassword function of the bosh-windows-stemcell-builder. This lack of entropy results in predictable password generation for Windows stemcells. An attacker with network access to the affected instances (specifically port 22/TCP) can exploit this predictability to perform a successful brute-force attack against the SSH service. Successful exploitation grants the attacker unauthorized remote access with the privileges of the generated account. The issue is resolved in version v2019.98.

Affected products

Cloud Foundry Foundation bosh-windows-stemcell-builder prior to v2019.98

Timeline

2026-07-08: advisory: Initial vulnerability report published by Cloud Foundry Foundation
2026-07-09: disclosed: CVE published to NVD dataset

References

https://www.cloudfoundry.org/blog/cve-2026-47831-cryptographically-weak-password-generation-in-bosh-windows-stemcell-builder-allows-remote-ssh-brute-force-attacks/

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