Sangoma FreePBX OS Command Injection
CVE-2025-64328 is a high-severity improper neutralization of special elements used in an OS command vulnerability in filestore from FreePBX, with a CVSS 3.1 base score of 7.2 out of 10. It can be exploited remotely over the network by an attacker with administrator privileges, without any action from a user. Affected filestore versions: >= 17.0.2.36, < 17.0.3. The record does not name a fixed version, so check the vendor advisory. CISA added it to the Known Exploited Vulnerabilities catalogue on February 3, 2026, which means attacks have been observed in the wild.
Attackers are already exploiting this vulnerability, according to CISA.
What to do
- Check which version of filestore you run against the affected versions below, and install the vendor's latest release.
- CISA's required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
- Read the advisory on github.com for workarounds and exact fixed builds.
Affected products and versions
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- HighAdministrator-level access is required first.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 8.6 | High | CNA (github.com) |
| CVSS 3.1 | 7.2 | High | NVD |
Official description
FreePBX Endpoint Manager is a module for managing telephony endpoints in FreePBX systems. In versions 17.0.2.36 and above before 17.0.3, the filestore module within the Administrative interface is vulnerable to a post-authentication command injection by an authenticated known user via the testconnection -> check_ssh_connect() function. An attacker can leverage this vulnerability to obtain remote access to the system as an asterisk user. This issue is fixed in version 17.0.3.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Neutralization of Special Elements used in an OS Command
The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command before it is sent to a downstream component.
How developers prevent this class of flaw
- If at all possible, use library calls rather than external processes to recreate the desired functionality.
- For any data that will be used to generate a command to be executed, keep as much of that data out of external control as possible. For example, in web applications, this may require storing the data locally in the session's state instead of sending it out to the client in a hidden form field.
- For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.
More Improper Neutralization of Special Elements used in an OS Command vulnerabilities (CWE-78)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: active, automatable: no, technical impact: total).
- Added to CISA's Known Exploited Vulnerabilities catalogue.
- Deadline for US federal agencies to remediate, set by CISA.
- Record last changed materially (score, affected products, status or references).
References
Advisories
Third-party and government advisories
- cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-64328Third Party Advisory, US Government Resource
Technical write-ups (may include proof of concept)
- fortinet.com/blog/threat-research/unveiling-the-weaponized-web-shell-encystphpExploit, Third Party Advisory
Other references
Recent Improper Neutralization of Special Elements used in an OS Command vulnerabilities
- 10.0 Critical severity
- 9.3 Critical severity
- 7.8 High severity
- 7.2 High severity
- 9.8 Critical severity
- 9.8 Critical severity
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