# CVE-2025-36421: Multiple vulnerabilities in IBM Controller

> An attacker can intercept sensitive information via man-in-the-middle attacks due to clear text transmission in IBM Controller.

- **Severity:** Medium 5.9 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 18 Sep 2026
- **Updated:** 19 Sep 2026
- **Also known as:** GHSA-4fr9-cr7w-7w6w

## What is CVE-2025-36421?

CVE-2025-36421 is a medium-severity vulnerability in IBM Controller, published on 18 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

IBM Controller 11.0.0 through 11.0.1 FP7, and 11.1.0 through 11.1.3 FP1 transmits data in clear text that could allow an attacker to obtain sensitive information using man in the middle techniques.

Weakness: CWE-319 (Cleartext Transmission of Sensitive Information)

## Which versions are affected by CVE-2025-36421?


## How do I fix CVE-2025-36421?

No fix has been published for CVE-2025-36421 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-36421 being exploited?

There is no known exploitation of CVE-2025-36421 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-36421 and fix it if it is affected.

What it is: CVE-2025-36421 is a medium-severity vulnerability in IBM Controller, published on 18 Sep 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-2025-36421 in the wild and no public exploit code.

Affected product: IBM Controller. 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-2025-36421/ (Markdown: https://insights.sbomify.com/CVE-2025-36421/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-36421
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-36421
- OSV: https://osv.dev/vulnerability/CVE-2025-36421

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-36421/
Summaries are generated and may contain mistakes; the official description above is the record.