# CVE-2023-49079: Misskey's missing signature validation allows arbitrary users to impersonate any remote user.

> Missing signature validation in Misskey allows arbitrary users to impersonate any remote user, leading to account takeover.

- **Severity:** Critical 9.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 29 Nov 2023
- **Updated:** 2 Aug 2024
- **Also known as:** GHSA-3f39-6537-3cgc

## What is CVE-2023-49079?

CVE-2023-49079 is a critical authentication bypass vulnerability in misskey-dev misskey, published on 29 Nov 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Misskey is an open source, decentralized social media platform. Misskey's missing signature validation allows arbitrary users to impersonate any remote user. This issue has been patched in version 2023.11.1-beta.1.

Weakness: CWE-347 (Improper Verification of Cryptographic Signature)

## Which versions are affected by CVE-2023-49079?

It affects 1 product.


Products: Misskey Misskey.

## How do I fix CVE-2023-49079?

No fix has been published for CVE-2023-49079 yet. Limit exposure of the affected software until one is available.

## Is CVE-2023-49079 being exploited?

There is no known exploitation of CVE-2023-49079 in the wild and no public exploit code.

## Other vulnerabilities in misskey-dev misskey

- [CVE-2025-25306](https://insights.sbomify.com/CVE-2025-25306/): Misskey's Incomplete Patch of CVE-2024-52591 Leads to Forgery of Federated Notes (critical 9.3)
- [CVE-2026-28431](https://insights.sbomify.com/CVE-2026-28431/): Misskey lacks proper authorization checks and input validation (critical 9.2)
- [CVE-2023-52139](https://insights.sbomify.com/CVE-2023-52139/): Misskey vulnerable to improper authorization when accessing with third-party application (critical 9.1)
- [CVE-2024-52590](https://insights.sbomify.com/CVE-2024-52590/): Missing validation allows spoofed profiles in Misskey (high 8.8)
- [CVE-2024-52591](https://insights.sbomify.com/CVE-2024-52591/): Missing validation allows spoofed profiles and notes in Misskey (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-49079 and fix it if it is affected.

What it is: CVE-2023-49079 is a critical authentication bypass vulnerability in misskey-dev misskey, published on 29 Nov 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2023-49079 in the wild and no public exploit code.

Affected product: misskey-dev misskey. 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-2023-49079/ (Markdown: https://insights.sbomify.com/CVE-2023-49079/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-49079
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-49079
- OSV: https://osv.dev/vulnerability/CVE-2023-49079

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-49079/
Summaries are generated and may contain mistakes; the official description above is the record.