# CVE-2025-2520: Dereferencing of an uninitialized pointer leads to denial of service.

> An attacker can cause a denial of service in Honeywell Experion PKS by exploiting an uninitialized pointer dereference in the EPA communications.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 10 Jul 2025
- **Updated:** 4 Aug 2025
- **Also known as:** GHSA-235q-27q4-67jx

## What is CVE-2025-2520?

CVE-2025-2520 is a high-severity vulnerability in Honeywell C300 PCNT02, published on 10 Jul 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The Honeywell Experion PKS contains an Uninitialized Variable in the common Epic Platform Analyzer (EPA) communications. An attacker could potentially exploit this vulnerability, leading to a Communication Channel Manipulation, which results in a dereferencing of an uninitialized pointer leading to a denial of service.

Honeywell recommends updating to the most recent version of 

Honeywell Experion PKS: 520.2 TCU9 HF1and 530.1 TCU3 HF1. The affected Experion PKS products are 

C300 PCNT02, EHB, EHPM, ELMM, Classic ENIM, ETN, FIM4, FIM8, PGM, and RFIM.  The Experion PKS versions affected are from 520.1 through 520.2 TCU9 and from 530 through 530 TCU3.

Weakness: CWE-457 (Use of Uninitialized Variable)

## Which versions are affected by CVE-2025-2520?


## How do I fix CVE-2025-2520?

No fix has been published for CVE-2025-2520 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-2520 being exploited?

There is no known exploitation of CVE-2025-2520 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-2520 and fix it if it is affected.

What it is: CVE-2025-2520 is a high-severity vulnerability in Honeywell C300 PCNT02, published on 10 Jul 2025. 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-2025-2520 in the wild and no public exploit code.

Affected product: Honeywell C300 PCNT02. 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-2025-2520/ (Markdown: https://insights.sbomify.com/CVE-2025-2520/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-2520
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-2520
- OSV: https://osv.dev/vulnerability/CVE-2025-2520

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-2520/
Summaries are generated and may contain mistakes; the official description above is the record.