CVE-2026-26978 (GCVE-0-2026-26978)

Vulnerability from cvelistv5 – Published: 2026-05-18 20:49 – Updated: 2026-05-20 03:55
VLAI
Title
Free PBX backup: Deserialization of Untrusted Data in admin/modules/backup/Models/BackupSplFileInfo.php
Summary
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.
Severity
8.6 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-19 00:00 UTC
CWE
  • CWE-502 - Deserialization of Untrusted Data
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7868 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
FreePBX security-reporting Affected: < 16.0.71
Affected: >= 17.0.0, < 17.0.6
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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