# CVE-2016-0821: Security feature bypass in n/a

> Attackers can bypass poison-pointer protection mechanisms in the Linux kernel by exploiting improper handling of uninitialized list entries relative to mmap_min_addr.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/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:** 12 Mar 2016
- **Updated:** 5 Aug 2024
- **Also known as:** DEBIAN-CVE-2016-0821, GHSA-9548-jjm6-2wmw, UBUNTU-CVE-2016-0821

## What is CVE-2016-0821?

CVE-2016-0821 is a medium-severity vulnerability in Google Android, published on 12 Mar 2016. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

The LIST_POISON feature in include/linux/poison.h in the Linux kernel before 4.3, as used in Android 6.0.1 before 2016-03-01, does not properly consider the relationship to the mmap_min_addr value, which makes it easier for attackers to bypass a poison-pointer protection mechanism by triggering the use of an uninitialized list entry, aka Android internal bug 26186802, a different vulnerability than CVE-2015-3636.

Weakness: CWE-908 (Use of Uninitialized Resource)

## Which versions are affected by CVE-2016-0821?

It affects 2 products.


Products: Google Android, Linux kernel.

## How do I fix CVE-2016-0821?

Apply the vendor's patch.

## Is CVE-2016-0821 being exploited?

There is no known exploitation of CVE-2016-0821 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-2016-0821 and fix it if it is affected.

What it is: CVE-2016-0821 is a medium-severity vulnerability in Google Android, published on 12 Mar 2016. 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-2016-0821 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-2016-0821/ (Markdown: https://insights.sbomify.com/CVE-2016-0821/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2016-0821
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2016-0821
- OSV: https://osv.dev/vulnerability/CVE-2016-0821

---
From sbomify Insights: https://insights.sbomify.com/CVE-2016-0821/
Summaries are generated and may contain mistakes; the official description above is the record.