# CVE-2016-8671: Information disclosure in n/a

> Remote attackers can predict secret keys due to improper modular exponentiation in MatrixSSL, compromising cryptographic security.

- **Severity:** Medium 5.9 (`CVSS:3.0/AV:N/AC:H/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:** 13 Jan 2017
- **Updated:** 6 Aug 2024
- **Also known as:** GHSA-8q3f-94v5-w475

## What is CVE-2016-8671?

CVE-2016-8671 is a medium-severity vulnerability in n/a, published on 13 Jan 2017. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The pstm_exptmod function in MatrixSSL 3.8.6 and earlier does not properly perform modular exponentiation, which might allow remote attackers to predict the secret key via unspecified vectors. NOTE: this vulnerability exists because of an incomplete fix for CVE-2016-6887.

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

## Which versions are affected by CVE-2016-8671?

It affects 1 product.


Products: Matrixssl Matrixssl.

## How do I fix CVE-2016-8671?

No fix has been published for CVE-2016-8671 yet. Limit exposure of the affected software until one is available.

## Is CVE-2016-8671 being exploited?

There is no known exploitation of CVE-2016-8671 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2019-14431](https://insights.sbomify.com/CVE-2019-14431/): Memory corruption in n/a (critical 9.8)
- [CVE-2019-13470](https://insights.sbomify.com/CVE-2019-13470/): Memory corruption in n/a (critical 9.8)
- [CVE-2019-10914](https://insights.sbomify.com/CVE-2019-10914/): Memory corruption in n/a (critical 9.8)
- [CVE-2016-6890](https://insights.sbomify.com/CVE-2016-6890/): Memory corruption in n/a (critical 9.8)
- [CVE-2022-43974](https://insights.sbomify.com/CVE-2022-43974/): Integer overflow in n/a (high 8.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2016-8671 and fix it if it is affected.

What it is: CVE-2016-8671 is a medium-severity vulnerability in n/a, published on 13 Jan 2017. 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-2016-8671 in the wild and no public exploit code.

Affected product: n/a. 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-2016-8671/ (Markdown: https://insights.sbomify.com/CVE-2016-8671/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2016-8671
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2016-8671
- OSV: https://osv.dev/vulnerability/CVE-2016-8671

---
From sbomify Insights: https://insights.sbomify.com/CVE-2016-8671/
Summaries are generated and may contain mistakes; the official description above is the record.