CVE-2026-26978
Free PBX backup: Deserialization of Untrusted Data in admin/modules/backup/Models/BackupSplFileInfo.php
Description
FreePBX is an open source IP PBX. In versions below 16.0.71 and 17.0.6, the backup module does not properly sanitize data during restore operations, potentially leading to compromise if the backup contains carefully crafted hostile data. During backup restore operations, FreePBX extracts selected files from a user-supplied tar archive. If a malicious file exists in the archive, it is read and passed directly to unserialize() without validation, class restrictions, or integrity checks. This issue allows Remote Code Execution during restoration of the backup as the web server user (typically asterisk or www-data). The attack does not require shell access, CLI access, or filesystem write permissions beyond the normal restore workflow. Authentication with a known username that has sufficient access permissions and/or write access to backup files is required. This issue has been fixed in versions 16.0.71 and 17.0.6.
INFO
Published Date :
May 18, 2026, 9:16 p.m.
Last Modified :
July 24, 2026, 1:10 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 4.0 | HIGH | [email protected] |
Solution
- Update FreePBX to version 16.0.71 or higher.
- Update FreePBX to version 17.0.6 or higher.
Public PoC/Exploit Available at Github
CVE-2026-26978 has a 2 public
PoC/Exploit available at Github.
Go to the Public Exploits tab to see the list.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-26978.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-26978 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-26978
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
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Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-26978 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-26978 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Translated by [email protected]
Jul. 24, 2026
Action Type Old Value New Value Added Translation Title: security-reporting de FreePBX, Description: FreePBX es una PBX IP de código abierto. En versiones anteriores a la 16.0.71 y 17.0.6, el módulo de copia de seguridad no sanea correctamente los datos durante las operaciones de restauración, lo que podría llevar a un compromiso si la copia de seguridad contiene datos hostiles cuidadosamente elaborados. Durante las operaciones de restauración de la copia de seguridad, FreePBX extrae archivos seleccionados de un archivo tar proporcionado por el usuario. Si existe un archivo malicioso en el archivo, se lee y se pasa directamente a unserialize() sin validación, restricciones de clase o comprobaciones de integridad. Este problema permite la Ejecución Remota de Código durante la restauración de la copia de seguridad como el usuario del servidor web (típicamente asterisk o www-data). El ataque no requiere acceso a shell, acceso CLI o permisos de escritura en el sistema de archivos más allá del flujo de trabajo de restauración normal. Se requiere Autenticación con un nombre de usuario conocido que tenga permisos de acceso suficientes y/o acceso de escritura a los archivos de copia de seguridad. Este problema ha sido solucionado en las versiones 16.0.71 y 17.0.6. -
CVE Modified by [email protected]
Jun. 17, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'FreePBX', 'product': 'security-reporting', 'versions': [{'status': 'affected', 'version': '< 16.0.71'}, {'status': 'affected', 'version': '>= 17.0.0, < 17.0.6'}]}] -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 17, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-26978', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-05-19T00:00:00+00:00'} -
New CVE Received by [email protected]
May. 18, 2026
Action Type Old Value New Value Added Description FreePBX is an open source IP PBX. In versions below 16.0.71 and 17.0.6, the backup module does not properly sanitize data during restore operations, potentially leading to compromise if the backup contains carefully crafted hostile data. During backup restore operations, FreePBX extracts selected files from a user-supplied tar archive. If a malicious file exists in the archive, it is read and passed directly to unserialize() without validation, class restrictions, or integrity checks. This issue allows Remote Code Execution during restoration of the backup as the web server user (typically asterisk or www-data). The attack does not require shell access, CLI access, or filesystem write permissions beyond the normal restore workflow. Authentication with a known username that has sufficient access permissions and/or write access to backup files is required. This issue has been fixed in versions 16.0.71 and 17.0.6. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CWE CWE-502 Added Reference https://github.com/FreePBX/backup/commit/45c57e1207cbf9fd1c5f76f8a3e72d204a69a472 Added Reference https://github.com/FreePBX/backup/commit/64781af5c80cce0cff21a981be4d8e6a7a71f2c4 Added Reference https://github.com/FreePBX/security-reporting/security/advisories/GHSA-5v7h-49gr-jcwr