# CVE-2022-26943: Weak PRNG entropy source used for authentication challenge generation in Motorola MTM5000

> Weak PRNG entropy allows attackers to predict authentication challenges, enabling unauthorized access to Motorola MTM5000 radios.

- **Severity:** High 8.8 (`CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:F/RL:U/RC:C/CR:H/IR:H/AR:H/MAV:A/MAC:L/MPR:N/MUI:N/MS:U/MC:H/MI:H/MA:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 19 Oct 2023
- **Updated:** 3 Aug 2024
- **Also known as:** GHSA-cj2w-wj5h-c44x

## What is CVE-2022-26943?

CVE-2022-26943 is a high-severity vulnerability in Motorola Mobile Radio, published on 19 Oct 2023. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

The Motorola MTM5000 series firmwares generate TETRA authentication challenges using a PRNG using a tick count register as its sole entropy source. Low boottime entropy and limited re-seeding of the pool renders the authentication challenge vulnerable to two attacks. First, due to the limited boottime pool entropy, an adversary can derive the contents of the entropy pool by an exhaustive search of possible values, based on an observed authentication challenge. Second, an adversary can use knowledge of the entropy pool to predict authentication challenges. As such, the unit is vulnerable to CVE-2022-24400.

Weakness: CWE-338 (Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG))

## Which versions are affected by CVE-2022-26943?

It affects 2 products.


Products: Motorola Mtm5400 Firmware, Motorola Mtm5500 Firmware.

## How do I fix CVE-2022-26943?

No fix has been published for CVE-2022-26943 yet. Limit exposure of the affected software until one is available.

## Is CVE-2022-26943 being exploited?

There is no known exploitation of CVE-2022-26943 in the wild and no public exploit code.

## Other vulnerabilities in Motorola Mobile Radio

- [CVE-2022-26941](https://insights.sbomify.com/CVE-2022-26941/): Format string vulnerability in AT+CTGL command in Motorola MTM5000 (critical 9.6)
- [CVE-2022-26942](https://insights.sbomify.com/CVE-2022-26942/): Multiple missing pointer validation checks in trusted execution module in Motorola MTM5000 (high 8.2)
- [CVE-2022-27813](https://insights.sbomify.com/CVE-2022-27813/): Unconfigured memory protection modules in Motorola MTM5000 (high 8.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2022-26943 and fix it if it is affected.

What it is: CVE-2022-26943 is a high-severity vulnerability in Motorola Mobile Radio, published on 19 Oct 2023. 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-2022-26943 in the wild and no public exploit code.

Affected product: Motorola Mobile Radio. 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-2022-26943/ (Markdown: https://insights.sbomify.com/CVE-2022-26943/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-26943
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-26943
- OSV: https://osv.dev/vulnerability/CVE-2022-26943

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-26943/
Summaries are generated and may contain mistakes; the official description above is the record.