# CVE-2016-0818: Security feature bypass in n/a

> Man-in-the-middle attackers can spoof servers by exploiting a flaw in Android's TrustManagerImpl certificate validation logic.

- **Severity:** Medium 5.9 (`CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 12 Mar 2016
- **Updated:** 5 Aug 2024
- **Also known as:** GHSA-gfmm-3f49-2hrh, UBUNTU-CVE-2016-0818

## What is CVE-2016-0818?

CVE-2016-0818 is a medium-severity vulnerability in Google Android, published on 12 Mar 2016. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The caching functionality in the TrustManagerImpl class in TrustManagerImpl.java in Conscrypt in Android 4.x before 4.4.4, 5.x before 5.1.1 LMY49H, and 6.x before 2016-03-01 mishandles the distinction between an intermediate CA and a trusted root CA, which allows man-in-the-middle attackers to spoof servers by leveraging access to an intermediate CA to issue a certificate, aka internal bug 26232830.

Weakness: CWE-345 (Insufficient Verification of Data Authenticity), CWE-254

## Which versions are affected by CVE-2016-0818?

It affects 1 product.


Products: Google Android.

## How do I fix CVE-2016-0818?

Apply the vendor's patch.

## Is CVE-2016-0818 being exploited?

There is no known exploitation of CVE-2016-0818 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-2016-0818 and fix it if it is affected.

What it is: CVE-2016-0818 is a medium-severity vulnerability in Google Android, published on 12 Mar 2016. 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-2016-0818 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-2016-0818/ (Markdown: https://insights.sbomify.com/CVE-2016-0818/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2016-0818
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2016-0818
- OSV: https://osv.dev/vulnerability/CVE-2016-0818

---
From sbomify Insights: https://insights.sbomify.com/CVE-2016-0818/
Summaries are generated and may contain mistakes; the official description above is the record.