# CVE-2026-65628: Infinite recursion (CPU denial-of-service) in JOSE.JWK.shared_secret/2 on mismatched key types


- **Severity:** Medium 5.9 (`CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Fix available:** Yes
- **Published:** 26 Oct 2026
- **Updated:** 26 Oct 2026
- **Also known as:** AZL-111155, DEBIAN-CVE-2026-65628, EEF-CVE-2026-65628, GHSA-fpj2-9h59-32pp, UBUNTU-CVE-2026-65628

## What is CVE-2026-65628?

CVE-2026-65628 is a medium-severity vulnerability in potatosalad jose, published on 26 Oct 2026. 

### Official description

jose_jwk:shared_secret/2 (exposed in Elixir as JOSE.JWK.shared_secret/2) derives an ECDH shared secret from two JWKs. Its first function clause only matches when both JWKs carry the same key type (kty) module, and its fallback clause re-invokes itself as shared_secret(from(YourJWK), from(MyJWK)). Because from/1 returns an already-parsed jose_jwk record unchanged, passing two JWKs whose key types differ (for example an EC key and an RSA key) makes the fallback clause re-enter with identical arguments, producing an unbounded tail-recursive loop that never returns and never crashes.

An application that derives a shared secret from an externally supplied peer public key without first checking that the peer key's type and curve match its own key can be driven into this loop by an attacker-controlled JWK, pinning an Erlang scheduler at 100% CPU. Repeated requests exhaust the available schedulers, resulting in a denial of service.

This issue affects jose: from 1.5.0 before 1.11.13.

Weakness: CWE-674 (Uncontrolled Recursion)

## Which versions are affected by CVE-2026-65628?

1 open source package ship an affected version, including jose.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `jose` | Hex | From 1.5.0 | 1.11.13 |

## How do I fix CVE-2026-65628?

Upgrade jose to 1.11.13 or later.

## Is CVE-2026-65628 being exploited?

There is no known exploitation of CVE-2026-65628 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-65628 and fix it if it is affected.

What it is: CVE-2026-65628 is a medium-severity vulnerability in potatosalad jose, published on 26 Oct 2026. 
Exploitation: There is no known exploitation of CVE-2026-65628 in the wild and no public exploit code.

Affected packages and fixed versions:
- jose (Hex): affected from 1.5.0; fixed in 1.11.13

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-2026-65628/ (Markdown: https://insights.sbomify.com/CVE-2026-65628/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-65628
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-65628
- OSV: https://osv.dev/vulnerability/CVE-2026-65628

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-65628/
Summaries are generated and may contain mistakes; the official description above is the record.