# CVE-2026-46452: Apache NimBLE: Mesh Proxy SAR reassembly unbounded append and unchecked failure

> Attackers can cause memory pressure and unstable parsing in Apache NimBLE via improper input validation in Mesh Proxy SAR reassembly.

- **Severity:** Medium 5.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 24 Jul 2026
- **Updated:** 24 Jul 2026
- **Also known as:** GHSA-wfj4-rqg3-9346

## What is CVE-2026-46452?

CVE-2026-46452 is a medium-severity denial of service vulnerability in Apache NimBLE, published on 24 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Improper Input Validation vulnerability in Apache NimBLE in Mesh Proxy SAR reassembly could result in passing broken data toward application resulting in memory pressure and unstable parsing behavior.

This issue affects Apache NimBLE: through 1.9.0.

Users are recommended to upgrade to version 1.10.0, which fixes the issue.

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2026-46452?

It affects 1 product.


Products: Apache Nimble.

## How do I fix CVE-2026-46452?

No fix has been published for CVE-2026-46452 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-46452 being exploited?

There is no known exploitation of CVE-2026-46452 in the wild and no public exploit code.

## Other vulnerabilities in Apache NimBLE

- [CVE-2026-45813](https://insights.sbomify.com/CVE-2026-45813/): Apache NimBLE: Incorrect data validation in BASS add/modify source operation (high 8.8)
- [CVE-2025-62235](https://insights.sbomify.com/CVE-2025-62235/): Apache Mynewt NimBLE: Incorrect handling of SMP Security Request could lead to undesirable pairing (high 8.1)
- [CVE-2026-45811](https://insights.sbomify.com/CVE-2026-45811/): Apache NimBLE: Buffer overflow in socket HCI transport (high 7.5)
- [CVE-2026-45815](https://insights.sbomify.com/CVE-2026-45815/): Apache NimBLE: Remote reachable assertion in ATT Read Multiple Variable Response handler (high 7.5)
- [CVE-2026-45816](https://insights.sbomify.com/CVE-2026-45816/): Apache NimBLE: NULL pointer dereference vulnerability in SMP LTK request (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-46452 and fix it if it is affected.

What it is: CVE-2026-46452 is a medium-severity denial of service vulnerability in Apache NimBLE, published on 24 Jul 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-2026-46452 in the wild and no public exploit code.

Affected product: Apache NimBLE. 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-2026-46452/ (Markdown: https://insights.sbomify.com/CVE-2026-46452/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-46452
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-46452
- OSV: https://osv.dev/vulnerability/CVE-2026-46452

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-46452/
Summaries are generated and may contain mistakes; the official description above is the record.