# CVE-2024-33531: Security feature bypass in n/a

> Attackers can bypass JWT signature verification in lua-resty-jwt by crafting tokens with specific encryption headers, allowing unauthorized access.

- **Severity:** High 8.1 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 24 Apr 2024
- **Updated:** 2 Aug 2024
- **Also known as:** GHSA-vvpg-5wfc-53jj

## What is CVE-2024-33531?

CVE-2024-33531 is a high-severity vulnerability in n/a, published on 24 Apr 2024. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

cdbattags lua-resty-jwt 0.2.3 allows attackers to bypass all JWT-parsing signature checks by crafting a JWT with an enc header with the value A256GCM.

Weakness: CWE-290 (Authentication Bypass by Spoofing)

## Which versions are affected by CVE-2024-33531?


## How do I fix CVE-2024-33531?

No fix has been published for CVE-2024-33531 yet. Limit exposure of the affected software until one is available.

## Is CVE-2024-33531 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2024-33531 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2024-33531 and fix it if it is affected.

What it is: CVE-2024-33531 is a high-severity vulnerability in n/a, published on 24 Apr 2024. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2024-33531 exists.

Affected product: n/a. 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-2024-33531/ (Markdown: https://insights.sbomify.com/CVE-2024-33531/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-33531
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-33531
- OSV: https://osv.dev/vulnerability/CVE-2024-33531

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-33531/
Summaries are generated and may contain mistakes; the official description above is the record.