# CVE-2021-0644: Information disclosure in Android

> A missing permission check in Android's SubscriptionController allows local attackers to retrieve trackable identifiers without user interaction.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 6 Oct 2021
- **Updated:** 3 Aug 2024
- **Also known as:** A-181053462, ASB-A-181053462, GHSA-x87c-8v42-cm55

## What is CVE-2021-0644?

CVE-2021-0644 is a medium-severity vulnerability in Google Android, published on 6 Oct 2021. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

In conditionallyRemoveIdentifiers of SubscriptionController.java, there is a possible way to retrieve a trackable identifier due to a missing permission check. This could lead to local information disclosure with User execution privileges needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android-11 Android-10Android ID: A-181053462

Weakness: CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor)

## Which versions are affected by CVE-2021-0644?

It affects 1 product.


Products: Google Android.

## How do I fix CVE-2021-0644?

Apply the vendor's patch.

## Is CVE-2021-0644 being exploited?

There is no known exploitation of CVE-2021-0644 in the wild and no public exploit code.

## Other vulnerabilities in Google Android

- [CVE-2026-58704](https://insights.sbomify.com/CVE-2026-58704/): Google Pixel Improper Authorization (high 8.8, exploited in the wild)
- [CVE-2025-48543](https://insights.sbomify.com/CVE-2025-48543/): Android Runtime Use-After-Free (high 8.8, exploited in the wild)
- [CVE-2023-35674](https://insights.sbomify.com/CVE-2023-35674/): Android Framework Privilege Escalation (high 8.8, exploited in the wild)
- [CVE-2025-48595](https://insights.sbomify.com/CVE-2025-48595/): Android Framework Integer Overflow (high 8.4, exploited in the wild)
- [CVE-2024-32896](https://insights.sbomify.com/CVE-2024-32896/): Android Pixel Privilege Escalation (high 8.1, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-0644 and fix it if it is affected.

What it is: CVE-2021-0644 is a medium-severity vulnerability in Google Android, published on 6 Oct 2021. 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-2021-0644 in the wild and no public exploit code.

Affected product: Google Android. 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-2021-0644/ (Markdown: https://insights.sbomify.com/CVE-2021-0644/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-0644
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-0644
- OSV: https://osv.dev/vulnerability/CVE-2021-0644

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-0644/
Summaries are generated and may contain mistakes; the official description above is the record.