# CVE-2025-66451: LibreChat's Improper Input Validation in Prompt Creation API Enables Unauthorized Permission Changes

> Attackers can modify prompt groups via unvalidated API requests, leading to unauthorized data changes and potential privilege escalation in LibreChat.

- **Severity:** Medium 5.3 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 11 Dec 2025
- **Updated:** 12 Dec 2025
- **Also known as:** GHSA-vpqq-5qr4-655h

## What is CVE-2025-66451?

CVE-2025-66451 is a medium-severity missing authorization vulnerability in Librechat Librechat, published on 11 Dec 2025. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

LibreChat is a ChatGPT clone with additional features. In versions 0.8.0 and below, when creating prompts, JSON requests are sent to define and modify the prompts via PATCH endpoint for prompt groups (/api/prompts/groups/:groupId). However, the request bodies are not sufficiently validated for proper input, enabling users to modify prompts in a way that was not intended as part of the front end system. The patchPromptGroup function passes req.body directly to updatePromptGroup() without filtering sensitive fields. This issue is fixed in version 0.8.1.

Weakness: CWE-915 (Improperly Controlled Modification of Dynamically-Determined Object Attributes), CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2025-66451?

It affects 1 product.


Products: Librechat Librechat.

## How do I fix CVE-2025-66451?

No fix has been published for CVE-2025-66451 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-66451 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-66451 exists.

## Other vulnerabilities in Librechat Librechat

- [CVE-2026-32625](https://insights.sbomify.com/CVE-2026-32625/): LibreChat Exfiltrates Server Secrets via MCP Server URL Injection (critical 9.6)
- [CVE-2024-11167](https://insights.sbomify.com/CVE-2024-11167/): Improper Access Control in danny-avila/librechat (critical 9.4)
- [CVE-2026-22252](https://insights.sbomify.com/CVE-2026-22252/): LibreChat MCP Stdio Remote Command Execution (critical 9.1)
- [CVE-2025-69222](https://insights.sbomify.com/CVE-2025-69222/): LibreChat is vulnerable to Server-Side Request Forgery due to missing restrictions (critical 9.1)
- [CVE-2024-41704](https://insights.sbomify.com/CVE-2024-41704/): Path traversal in n/a (critical 9.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-66451 and fix it if it is affected.

What it is: CVE-2025-66451 is a medium-severity missing authorization vulnerability in Librechat Librechat, published on 11 Dec 2025. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-66451 exists.

Affected product: Librechat Librechat. 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-2025-66451/ (Markdown: https://insights.sbomify.com/CVE-2025-66451/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-66451
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-66451
- OSV: https://osv.dev/vulnerability/CVE-2025-66451

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-66451/
Summaries are generated and may contain mistakes; the official description above is the record.