# CVE-2025-66039: FreePBX Endpoint Manager Allows Unauthenticated Logins to Administrator Control Panel via Forged Basic Auth Header

> Attackers can bypass authentication and gain administrator access to the FreePBX Endpoint Manager control panel by forging a Basic Auth header when webserver authentication is enabled.

- **Severity:** Critical 9.3 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 9 Dec 2025
- **Updated:** 26 Feb 2026
- **Also known as:** GHSA-9jvh-mv6x-w698

## What is CVE-2025-66039?

CVE-2025-66039 is a critical authentication bypass vulnerability in Sangoma Freepbx, published on 9 Dec 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

FreePBX Endpoint Manager is a module for managing telephony endpoints in FreePBX systems. Versions are vulnerable to authentication bypass when the authentication type is set to "webserver." When providing an Authorization header with an arbitrary value, a session is associated with the target user regardless of valid credentials. This issue is fixed in versions 16.0.44 and 17.0.23.

Weakness: CWE-287 (Improper Authentication)

## Which versions are affected by CVE-2025-66039?

It affects 1 product.


Products: Sangoma Freepbx.

## How do I fix CVE-2025-66039?

No fix has been published for CVE-2025-66039 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-66039 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-66039 exists.

Public exploit code:

- This vulnerability allows both authenticated and unauthenticated remote attackers to execute remote code on vulnerable FreePBX instances. These issues have been fixed in FreePBX versions 16.0.42, 16.0.92, 17.0.6, and 17.0.22. It's important to note that this authentication bypass vulnerability is not present in the default FreePBX configuration. (github_poc): https://github.com/BimBoxH4/CVE-2025-66039_CVE-2025-61675_CVE-2025-61678_reePBX
- This repository documents three security vulnerabilities discovered in FreePBX (CVE-2025-66039, CVE-2025-61678, CVE-2025-61675), including analysis, impact, and proof-of-concept details for security research and awareness purposes. (github_poc): https://github.com/cyberleelawat/FreePBX-Multiple-CVEs-2025
- FreePBX Custom Extension SQL Injection (metasploit)
- FreePBX endpoint SQLi to RCE (metasploit)
- FreePBX firmware file upload (metasploit)

## Other vulnerabilities in Sangoma Freepbx

- [CVE-2025-57819](https://insights.sbomify.com/CVE-2025-57819/): Sangoma FreePBX Authentication Bypass (critical 10.0, exploited in the wild)
- [CVE-2019-19006](https://insights.sbomify.com/CVE-2019-19006/): Sangoma FreePBX Improper Authentication (critical 9.8, exploited in the wild)
- [CVE-2026-73663](https://insights.sbomify.com/CVE-2026-73663/): FreePBX: Unauthenticated SQL injection in FreePBX missedcall via inbound Caller ID name leads to administrator takeover (critical 9.3)
- [CVE-2026-73665](https://insights.sbomify.com/CVE-2026-73665/): FreePBX UCP: Unauthenticated remote code execution via socket.io namespace auth bypass and AMI action injection (critical 9.3)
- [CVE-2026-46376](https://insights.sbomify.com/CVE-2026-46376/): FreePBX: Unauthenticated Use of Hard-Coded Credentials Vulnerability in FreePBX UCP Interface (critical 9.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-66039 and fix it if it is affected.

What it is: CVE-2025-66039 is a critical authentication bypass vulnerability in Sangoma Freepbx, published on 9 Dec 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-66039 exists.

Affected product: Sangoma Freepbx. 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-2025-66039/ (Markdown: https://insights.sbomify.com/CVE-2025-66039/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-66039
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-66039
- OSV: https://osv.dev/vulnerability/CVE-2025-66039

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-66039/
Summaries are generated and may contain mistakes; the official description above is the record.