# CVE-2026-10512: X25519 x86_64 assembly final reduction leaves non-canonical field element

> A flaw in wolfSSL's X25519 assembly implementation may produce incorrect shared secrets due to non-canonical field elements, compromising cryptographic integrity.

- **Severity:** Low 2.3 (`CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 25 Jun 2026
- **Updated:** 26 Jun 2026
- **Also known as:** DEBIAN-CVE-2026-10512, GHSA-gjm7-vch5-hch8, JLSEC-2026-695, UBUNTU-CVE-2026-10512

## What is CVE-2026-10512?

CVE-2026-10512 is a low-severity vulnerability in Wolfssl Wolfssl, published on 25 Jun 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

The X25519 x86_64 assembly implementation fails to clear the most significant bit during the final modular reduction, so the computed result may not be fully reduced modulo the field prime 2^255 - 19. This can leave the field element in a non-canonical form, producing an incorrect result from the scalar multiplication and potentially a wrong shared secret. The final carry-propagation chains in the x64 and AVX2 reduction routines could overflow into the top bit, and the high limb was not masked afterward, so the 255-bit field element was left non-canonical.

Weakness: CWE-682 (Incorrect Calculation)

## Which versions are affected by CVE-2026-10512?

It affects 1 product.


Products: Wolfssl Wolfssl.

## How do I fix CVE-2026-10512?

Apply the vendor's patch.

## Is CVE-2026-10512 being exploited?

There is no known exploitation of CVE-2026-10512 in the wild and no public exploit code.

## Other vulnerabilities in Wolfssl Wolfssl

- [CVE-2024-5991](https://insights.sbomify.com/CVE-2024-5991/): Buffer overread in domain name matching (critical 10.0)
- [CVE-2021-37155](https://insights.sbomify.com/CVE-2021-37155/): Security feature bypass in n/a (critical 9.8)
- [CVE-2020-36177](https://insights.sbomify.com/CVE-2020-36177/): Memory corruption in n/a (critical 9.8)
- [CVE-2014-2896](https://insights.sbomify.com/CVE-2014-2896/): Memory corruption in n/a (critical 9.8)
- [CVE-2014-2897](https://insights.sbomify.com/CVE-2014-2897/): Memory corruption in n/a (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-10512 and fix it if it is affected.

What it is: CVE-2026-10512 is a low-severity vulnerability in Wolfssl Wolfssl, published on 25 Jun 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-10512 in the wild and no public exploit code.

Affected product: Wolfssl Wolfssl. 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-2026-10512/ (Markdown: https://insights.sbomify.com/CVE-2026-10512/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-10512
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-10512
- OSV: https://osv.dev/vulnerability/CVE-2026-10512

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-10512/
Summaries are generated and may contain mistakes; the official description above is the record.