# CVE-2021-31576: Missing authorization in EN7528, EN7580

> A missing permission check in MediaTek Boa allows remote attackers to disclose information without user interaction or privileges.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 6 Feb 2023
- **Updated:** 3 Aug 2024
- **Also known as:** GHSA-vm3q-7657-hf38

## What is CVE-2021-31576?

CVE-2021-31576 is a high-severity missing authorization vulnerability in MediaTek, Inc. EN7528, EN7580, published on 6 Feb 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

In Boa, there is a possible information disclosure due to a missing permission check. This could lead to remote information disclosure to a proximal attacker with no additional execution privileges needed. User interaction is not needed for exploitation. Patch ID: A20210008; Issue ID: OSBNB00123241.

Weakness: CWE-862 (Missing Authorization)

## Which versions are affected by CVE-2021-31576?

It affects 2 products.


Products: Mediatek En7528 Firmware, Mediatek En7580 Firmware.

## How do I fix CVE-2021-31576?

No fix has been published for CVE-2021-31576 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-31576 being exploited?

There is no known exploitation of CVE-2021-31576 in the wild and no public exploit code.

## Other vulnerabilities in MediaTek, Inc. EN7528, EN7580

- [CVE-2021-31573](https://insights.sbomify.com/CVE-2021-31573/): Command injection in EN7528, EN7580 (critical 9.8)
- [CVE-2021-31574](https://insights.sbomify.com/CVE-2021-31574/): Command injection in EN7528, EN7580 (critical 9.8)
- [CVE-2021-31575](https://insights.sbomify.com/CVE-2021-31575/): Command injection in EN7528, EN7580 (critical 9.8)
- [CVE-2021-31577](https://insights.sbomify.com/CVE-2021-31577/): Missing authorization in EN7528, EN7580 (critical 9.8)
- [CVE-2021-31578](https://insights.sbomify.com/CVE-2021-31578/): Memory corruption in EN7528, EN7580 (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-31576 and fix it if it is affected.

What it is: CVE-2021-31576 is a high-severity missing authorization vulnerability in MediaTek, Inc. EN7528, EN7580, published on 6 Feb 2023. 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-2021-31576 in the wild and no public exploit code.

Affected product: MediaTek, Inc. EN7528, EN7580. 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-2021-31576/ (Markdown: https://insights.sbomify.com/CVE-2021-31576/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-31576
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-31576
- OSV: https://osv.dev/vulnerability/CVE-2021-31576

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-31576/
Summaries are generated and may contain mistakes; the official description above is the record.