# CVE-2019-16910: Weak cryptography in n/a

> Insufficient entropy in deterministic ECDSA blinding allows private key recovery via side-channel attacks when signing the same message repeatedly.

- **Severity:** Medium 5.3 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:R/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:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 26 Sep 2019
- **Updated:** 5 Aug 2024
- **Also known as:** ALPINE-CVE-2019-16910, DEBIAN-CVE-2019-16910, GHSA-jg4p-c829-4q39, JLSEC-2025-198, UBUNTU-CVE-2019-16910

## What is CVE-2019-16910?

CVE-2019-16910 is a medium-severity vulnerability in Arm Mbed Tls, published on 26 Sep 2019. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

Arm Mbed TLS before 2.19.0 and Arm Mbed Crypto before 2.0.0, when deterministic ECDSA is enabled, use an RNG with insufficient entropy for blinding, which might allow an attacker to recover a private key via side-channel attacks if a victim signs the same message many times. (For Mbed TLS, the fix is also available in versions 2.7.12 and 2.16.3.)

## Which versions are affected by CVE-2019-16910?

It affects 5 products.


Products: Arm Mbed Crypto, Arm Mbed Tls, Debian Debian Linux, Fedoraproject Fedora, Trustedfirmware Mbed Tls.

## How do I fix CVE-2019-16910?

Upgrade to a fixed version.

## Is CVE-2019-16910 being exploited?

There is no known exploitation of CVE-2019-16910 in the wild and no public exploit code.

## Other vulnerabilities in Arm Mbed Tls

- [CVE-2024-28960](https://insights.sbomify.com/CVE-2024-28960/): Other in n/a (high 8.2)
- [CVE-2020-10941](https://insights.sbomify.com/CVE-2020-10941/): Information disclosure in n/a (medium 5.9)
- [CVE-2019-18222](https://insights.sbomify.com/CVE-2019-18222/): Information disclosure in n/a (medium 4.7)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2019-16910 and fix it if it is affected.

What it is: CVE-2019-16910 is a medium-severity vulnerability in Arm Mbed Tls, published on 26 Sep 2019. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2019-16910 in the wild and no public exploit code.

Affected product: Arm Mbed Tls. 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-2019-16910/ (Markdown: https://insights.sbomify.com/CVE-2019-16910/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-16910
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-16910
- OSV: https://osv.dev/vulnerability/CVE-2019-16910

---
From sbomify Insights: https://insights.sbomify.com/CVE-2019-16910/
Summaries are generated and may contain mistakes; the official description above is the record.