# CVE-2026-32135: NanoMQ has Heap Buffer Overflow in URI Parameter Parsing

> A heap buffer overflow in NanoMQ's REST API allows remote attackers to execute arbitrary code or cause denial of service via crafted HTTP requests.

- **Severity:** High 7.7 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 20 Apr 2026
- **Updated:** 21 Apr 2026
- **Also known as:** GHSA-6w96-9qw7-m599

## What is CVE-2026-32135?

CVE-2026-32135 is a high-severity memory corruption vulnerability in nanomq, published on 20 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

NanoMQ MQTT Broker (NanoMQ) is an all-around Edge Messaging Platform. Versions prior to 0.24.11 have a remotely triggerable heap buffer overflow in the `uri_param_parse` function of NanoMQ's REST API. The vulnerability occurs due to an off-by-one error when allocating memory for query parameter keys and values, allowing an attacker to write a null byte beyond the allocated buffer. This can be triggered via a crafted HTTP request. Version 0.24.11 patches the issue.

Weakness: CWE-122 (Heap-based Buffer Overflow)

## Which versions are affected by CVE-2026-32135?

It affects 1 product.


Products: Emqx Nanomq.

## How do I fix CVE-2026-32135?

No fix has been published for CVE-2026-32135 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-32135 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-32135 exists.

## Other vulnerabilities in nanomq

- [CVE-2024-42655](https://insights.sbomify.com/CVE-2024-42655/): Missing authorization in n/a (high 8.8)
- [CVE-2025-59947](https://insights.sbomify.com/CVE-2025-59947/): NanoMQ has Buffer Overflow (high 8.5)
- [CVE-2023-34488](https://insights.sbomify.com/CVE-2023-34488/): Memory corruption in n/a (high 8.0)
- [CVE-2026-36590](https://insights.sbomify.com/CVE-2026-36590/): Denial of service in n/a (high 7.5)
- [CVE-2026-21888](https://insights.sbomify.com/CVE-2026-21888/): MQTT v5 Variable Byte Integer parsing out-of-bounds: get_var_integer() (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-32135 and fix it if it is affected.

What it is: CVE-2026-32135 is a high-severity memory corruption vulnerability in nanomq, published on 20 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-32135 exists.

Affected product: nanomq. 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-2026-32135/ (Markdown: https://insights.sbomify.com/CVE-2026-32135/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-32135
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-32135
- OSV: https://osv.dev/vulnerability/CVE-2026-32135

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-32135/
Summaries are generated and may contain mistakes; the official description above is the record.