# CVE-2026-102552: Improper verification of the source of a communication channel in FreeRTOS-Plus-TCP DNS resolver

> Remote attackers can poison the DNS cache of FreeRTOS devices by forging replies, requiring an upgrade and enabling a specific configuration flag.

- **Severity:** High 8.2 (`CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/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:** 16 Oct 2026
- **Updated:** 19 Oct 2026
- **Also known as:** GHSA-h4fw-pv82-p7h5

## What is CVE-2026-102552?

CVE-2026-102552 is a high-severity vulnerability in FreeRTOS-Plus-TCP, published on 16 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Improper verification of the source of a communication channel in the DNS resolver in Amazon FreeRTOS-Plus-TCP before V4.4.2 might allow remote third-party to insert a chosen address into the device's DNS cache via a forged DNS reply.

To remediate this issue, users should upgrade to version V4.4.2 and enable ipconfigDNS_CHECK_REPLY_SOURCE_IP.

Weakness: CWE-940 (Improper Verification of Source of a Communication Channel)

## Which versions are affected by CVE-2026-102552?


## How do I fix CVE-2026-102552?

No fix has been published for CVE-2026-102552 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-102552 being exploited?

There is no known exploitation of CVE-2026-102552 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-102552 and fix it if it is affected.

What it is: CVE-2026-102552 is a high-severity vulnerability in FreeRTOS-Plus-TCP, published on 16 Oct 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-2026-102552 in the wild and no public exploit code.

Affected product: FreeRTOS-Plus-TCP. 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-2026-102552/ (Markdown: https://insights.sbomify.com/CVE-2026-102552/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-102552
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-102552
- OSV: https://osv.dev/vulnerability/CVE-2026-102552

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-102552/
Summaries are generated and may contain mistakes; the official description above is the record.