# CVE-2025-6391: JSON Web Token (JWT) Exposure in Log Files

> Attackers with log access can steal JWTs from Brocade ASCG logs, enabling session hijacking and unauthorized access.

- **Severity:** High 7.1 (`CVSS:4.0/AV:L/AC:L/AT:P/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 17 Jul 2025
- **Updated:** 18 Jul 2025
- **Also known as:** GHSA-cqgv-gr59-9qf6

## What is CVE-2025-6391?

CVE-2025-6391 is a high-severity vulnerability in Broadcom Brocade ASCG, published on 17 Jul 2025. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

Brocade ASCG before 3.3.0 logs JSON 
Web Tokens (JWT) in log files. An attacker with access to the log files 
 can withdraw the unencrypted tokens with security implications, such as
 unauthorized access, session hijacking, and information disclosure.

Weakness: CWE-532 (Insertion of Sensitive Information into Log File)

## Which versions are affected by CVE-2025-6391?

It affects 1 product.


Products: Broadcom Brocade Active Support Connectivity Gateway.

## How do I fix CVE-2025-6391?

No fix has been published for CVE-2025-6391 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-6391 being exploited?

There is no known exploitation of CVE-2025-6391 in the wild and no public exploit code.

## Other vulnerabilities in Broadcom Brocade ASCG

- [CVE-2026-85421](https://insights.sbomify.com/CVE-2026-85421/): Missing authorization in Brocade Active Support Connectivity Gateway (high 8.7)
- [CVE-2026-85489](https://insights.sbomify.com/CVE-2026-85489/): Missing authorization in Brocade Active Support Connectivity Gateway (high 8.7)
- [CVE-2026-85423](https://insights.sbomify.com/CVE-2026-85423/): A vulnerability has been identified in the data collection service of Brocade ASCG versions before 3.5.0. (high 8.6)
- [CVE-2026-85486](https://insights.sbomify.com/CVE-2026-85486/): Code injection in Brocade Active Support Connectivity Gateway (high 8.6)
- [CVE-2026-85487](https://insights.sbomify.com/CVE-2026-85487/): Path traversal in Brocade Active Support Connectivity Gateway (high 8.6)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-6391 and fix it if it is affected.

What it is: CVE-2025-6391 is a high-severity vulnerability in Broadcom Brocade ASCG, published on 17 Jul 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2025-6391 in the wild and no public exploit code.

Affected product: Broadcom Brocade ASCG. 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-2025-6391/ (Markdown: https://insights.sbomify.com/CVE-2025-6391/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-6391
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-6391
- OSV: https://osv.dev/vulnerability/CVE-2025-6391

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-6391/
Summaries are generated and may contain mistakes; the official description above is the record.