CVE-2026-26978

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.

CVSS

No CVSS.

References

Link	Resource
https://github.com/FreePBX/backup/commit/45c57e1207cbf9fd1c5f76f8a3e72d204a69a472
https://github.com/FreePBX/backup/commit/64781af5c80cce0cff21a981be4d8e6a7a71f2c4
https://github.com/FreePBX/security-reporting/security/advisories/GHSA-5v7h-49gr-jcwr

Configurations

No configuration.

History

18 May 2026, 21:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-18 21:16

Updated : 2026-05-19 15:04

NVD link : CVE-2026-26978

Mitre link : CVE-2026-26978

CVE.ORG link : CVE-2026-26978

JSON object : View

Products Affected

No product.

CWE

CWE-502

Deserialization of Untrusted Data

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