# CVE-2026-9030: Authenticated Denial-of-Service in HTTPD Service in TP-Link Archer A6

> Authenticated attackers can crash the HTTPD service or reboot the device by exploiting a race condition in systool instruction handling.

- **Severity:** Medium 6.8 (`CVSS:4.0/AV:A/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 7 Aug 2026
- **Updated:** 10 Aug 2026
- **Also known as:** GHSA-r6p4-crm5-rwvh

## What is CVE-2026-9030?

CVE-2026-9030 is a medium-severity vulnerability in TP-Link Systems Inc. Archer A6 v4, published on 7 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A denial-of-service
vulnerability exists in httpd service on Archer A6 v4 where the asynchronous systool
instruction handlng path in httpd does not properly synchronize or safely manage
concurrent systool operations.  

By sending
crafted systool instructions through the asynchronous request path, successful
exploitation may cause the httpd process or device management service to crash
and may result in temporary loss of access to the web management interface or
device reboot.

Weakness: CWE-362 (Concurrent Execution using Shared Resource with Improper Synchronization)

## Which versions are affected by CVE-2026-9030?


## How do I fix CVE-2026-9030?

No fix has been published for CVE-2026-9030 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-9030 being exploited?

There is no known exploitation of CVE-2026-9030 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-9030 and fix it if it is affected.

What it is: CVE-2026-9030 is a medium-severity vulnerability in TP-Link Systems Inc. Archer A6 v4, published on 7 Aug 2026. 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-2026-9030 in the wild and no public exploit code.

Affected product: TP-Link Systems Inc. Archer A6 v4. 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-2026-9030/ (Markdown: https://insights.sbomify.com/CVE-2026-9030/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-9030
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-9030
- OSV: https://osv.dev/vulnerability/CVE-2026-9030

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-9030/
Summaries are generated and may contain mistakes; the official description above is the record.