# GHSA-h533-5v22-8vcp: firebase/php-jwt: "None" Algorithm treated as valid on tokens

> Attackers can bypass JWT verification by using the 'None' algorithm, allowing unauthorized access to protected resources.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 15 May 2024

## What is GHSA-h533-5v22-8vcp?

GHSA-h533-5v22-8vcp is an authentication bypass vulnerability in firebase/php-jwt, published on 15 May 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Several widely-used JSON Web Token (JWT) libraries, including node-jsonwebtoken, pyjwt, namshi/jose, php-jwt, and jsjwt, are affected by critical vulnerabilities that could allow attackers to bypass the verification step when using asymmetric keys (RS256, RS384, RS512, ES256, ES384, ES512).

## Which versions are affected by GHSA-h533-5v22-8vcp?

2 open source packages ship an affected version, including firebase/php-jwt.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `firebase/php-jwt` | Packagist | All versions | 2.0.0 |
| `firebase/php-jwt` | Packagist | All versions | 2.0.0 |

## How do I fix GHSA-h533-5v22-8vcp?

Upgrade firebase/php-jwt to 2.0.0 or later.

## Is GHSA-h533-5v22-8vcp being exploited?

There is no known exploitation of GHSA-h533-5v22-8vcp in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for GHSA-h533-5v22-8vcp and fix it if it is affected.

What it is: GHSA-h533-5v22-8vcp is an authentication bypass vulnerability in firebase/php-jwt, published on 15 May 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of GHSA-h533-5v22-8vcp in the wild and no public exploit code.

Affected packages and fixed versions:
- firebase/php-jwt (Packagist): affected all versions; fixed in 2.0.0
- firebase/php-jwt (Packagist): affected all versions; fixed in 2.0.0

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/GHSA-h533-5v22-8vcp/ (Markdown: https://insights.sbomify.com/GHSA-h533-5v22-8vcp/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/GHSA-h533-5v22-8vcp

---
From sbomify Insights: https://insights.sbomify.com/GHSA-h533-5v22-8vcp/
Summaries are generated and may contain mistakes; the official description above is the record.