# CVE-2026-2930: Tenda A18 Httpd Service UploadCfg webCgiGetUploadFile stack-based overflow

> Remote attackers can trigger a stack-based buffer overflow in the Tenda A18 router's Httpd service via the UploadCfg endpoint, potentially leading to code execution.

- **Severity:** Medium 5.3 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 22 Feb 2026
- **Updated:** 27 Feb 2026
- **Also known as:** GHSA-c5fm-9xmx-m8v3

## What is CVE-2026-2930?

CVE-2026-2930 is a medium-severity memory corruption vulnerability in Tenda A18, published on 22 Feb 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

A vulnerability was identified in Tenda A18 15.13.07.13. The affected element is the function webCgiGetUploadFile of the file /cgi-bin/UploadCfg of the component Httpd Service. Such manipulation of the argument boundary leads to stack-based buffer overflow. The attack can be executed remotely. The exploit is publicly available and might be used.

Weakness: CWE-121 (Stack-based Buffer Overflow), CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer)

## Which versions are affected by CVE-2026-2930?

It affects 1 product.


Products: Tenda A18 Firmware.

## How do I fix CVE-2026-2930?

No fix has been published for CVE-2026-2930 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-2930 being exploited?

There is no known exploitation of CVE-2026-2930 in the wild and no public exploit code.

## Other vulnerabilities in Tenda A18

- [CVE-2023-50585](https://insights.sbomify.com/CVE-2023-50585/): Memory corruption in n/a (critical 9.8)
- [CVE-2024-32305](https://insights.sbomify.com/CVE-2024-32305/): Memory corruption in n/a (high 8.8)
- [CVE-2026-2876](https://insights.sbomify.com/CVE-2026-2876/): Tenda A18 setBlackRule parse_macfilter_rule stack-based overflow (high 8.7)
- [CVE-2026-2877](https://insights.sbomify.com/CVE-2026-2877/): Tenda A18 Httpd Service WifiExtraSet strcpy stack-based overflow (high 8.7)
- [CVE-2023-39827](https://insights.sbomify.com/CVE-2023-39827/): Memory corruption in n/a (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-2930 and fix it if it is affected.

What it is: CVE-2026-2930 is a medium-severity memory corruption vulnerability in Tenda A18, published on 22 Feb 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-2930 in the wild and no public exploit code.

Affected product: Tenda A18. 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-2026-2930/ (Markdown: https://insights.sbomify.com/CVE-2026-2930/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-2930
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-2930
- OSV: https://osv.dev/vulnerability/CVE-2026-2930

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-2930/
Summaries are generated and may contain mistakes; the official description above is the record.