# CVE-2026-40965: Information disclosure in CF Deployment

> Attackers can extract EC private keys from the public token_keys endpoint, enabling JWT forgery and authentication bypass in Cloud Foundry deployments using EC keys.

- **Severity:** Critical 10.0 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:L/SC:H/SI:H/SA:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 1 Jun 2026
- **Updated:** 3 Jun 2026
- **Also known as:** GHSA-qc5f-2h9q-7m2g

## What is CVE-2026-40965?

CVE-2026-40965 is a critical vulnerability in Cloud Foundry Foundation CF Deployment, published on 1 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Cloud Foundry UAA versions v76.12.0 through v78.12.0 are vulnerable to a private key exposure. The server contains a vulnerability where EC (Elliptic Curve) private keys are inadvertently exposed through the public /token_keys endpoint. This endpoint is designed to provide public key material for JWT token verification but incorrectly exposes private key components for EC keys. The vulnerability affects deployments using EC keys for JWT token signing. The vulnerability does not affect RSA key configurations, only deployments using EC keys for JWT signing.

Affected versions:
- uaa_release: v76.12.0 through v78.12.0 (inclusive); fixed in v78.13.0 or later
- CF Deployment: v30.0.0 through v56.0.0 (inclusive); fixed in v56.1.0 or later (bundles uaa_release v78.13.0)

Weakness: CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor)

## Which versions are affected by CVE-2026-40965?


## How do I fix CVE-2026-40965?

No fix has been published for CVE-2026-40965 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-40965 being exploited?

There is no known exploitation of CVE-2026-40965 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-40965 and fix it if it is affected.

What it is: CVE-2026-40965 is a critical vulnerability in Cloud Foundry Foundation CF Deployment, published on 1 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-40965 in the wild and no public exploit code.

Affected product: Cloud Foundry Foundation CF Deployment. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-40965/ (Markdown: https://insights.sbomify.com/CVE-2026-40965/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-40965
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-40965
- OSV: https://osv.dev/vulnerability/CVE-2026-40965

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-40965/
Summaries are generated and may contain mistakes; the official description above is the record.