# CVE-2025-13926: Contemporary Controls BASC 20T Reliance on Untrusted Inputs in a Security Decision

> Attackers can sniff network traffic to forge packets and make arbitrary requests to the BASC 20T controller, bypassing security controls.

- **Severity:** Critical 9.3 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 9 Apr 2026
- **Updated:** 10 Apr 2026
- **Also known as:** GHSA-5wpm-jgqp-3v9m

## What is CVE-2025-13926?

CVE-2025-13926 is a critical vulnerability in Contemporary Controls BASControl20, published on 9 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

An attacker could use data obtained by sniffing the network traffic to 
forge packets in order to make arbitrary requests to Contemporary 
Controls BASC 20T.

Weakness: CWE-807 (Reliance on Untrusted Inputs in a Security Decision)

## Which versions are affected by CVE-2025-13926?


## How do I fix CVE-2025-13926?

No fix has been published for CVE-2025-13926 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-13926 being exploited?

There is no known exploitation of CVE-2025-13926 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-13926 and fix it if it is affected.

What it is: CVE-2025-13926 is a critical vulnerability in Contemporary Controls BASControl20, published on 9 Apr 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-2025-13926 in the wild and no public exploit code.

Affected product: Contemporary Controls BASControl20. 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-2025-13926/ (Markdown: https://insights.sbomify.com/CVE-2025-13926/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-13926
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-13926
- OSV: https://osv.dev/vulnerability/CVE-2025-13926

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-13926/
Summaries are generated and may contain mistakes; the official description above is the record.