# CVE-2026-5527: Tenda 4G03 Pro ECDSA P-256 Private Key server.key hard-coded key

> Attackers can exploit a hard-coded ECDSA private key in Tenda 4G03 Pro routers to bypass security controls and access sensitive data.

- **Severity:** Medium 6.9 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/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:** 4 Apr 2026
- **Updated:** 6 Apr 2026
- **Also known as:** GHSA-pgjq-fxv2-9p7v

## What is CVE-2026-5527?

CVE-2026-5527 is a medium-severity vulnerability in Tenda 4G03 Pro, published on 4 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A weakness has been identified in Tenda 4G03 Pro 1.0/1.0re/01.bin/04.03.01.53. Affected by this issue is some unknown functionality of the file /etc/www/pem/server.key of the component ECDSA P-256 Private Key Handler. This manipulation causes use of hard-coded cryptographic key
 . It is possible to initiate the attack remotely.

Weakness: CWE-321 (Use of Hard-coded Cryptographic Key), CWE-320

## Which versions are affected by CVE-2026-5527?

It affects 1 product.


Products: Tenda 4g03 Pro Firmware.

## How do I fix CVE-2026-5527?

No fix has been published for CVE-2026-5527 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-5527 being exploited?

There is no known exploitation of CVE-2026-5527 in the wild and no public exploit code.

## Other vulnerabilities in Tenda 4G03 Pro

- [CVE-2026-5526](https://insights.sbomify.com/CVE-2026-5526/): Tenda 4G03 Pro httpd access control (medium 6.9)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-5527 and fix it if it is affected.

What it is: CVE-2026-5527 is a medium-severity vulnerability in Tenda 4G03 Pro, published on 4 Apr 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-2026-5527 in the wild and no public exploit code.

Affected product: Tenda 4G03 Pro. 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-2026-5527/ (Markdown: https://insights.sbomify.com/CVE-2026-5527/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-5527
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-5527
- OSV: https://osv.dev/vulnerability/CVE-2026-5527

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-5527/
Summaries are generated and may contain mistakes; the official description above is the record.