CVE-2026-26978
What it is
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.
At a glance
- Exploitability
- Can be exploited over the network with a low-privilege account. High risk of data exposure, data tampering.
- Exploit odds
- 0.9% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.9% in the next 30 days (EPSS).
- Severity: 8.6 HIGH (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.9% · EPSS, next 30 days
- Weakness
- CWE-502 · Unsafe deserialization
- Record status
- Deferred
Attack profile CVSS 4.0 · 8.6
- Attack vector
- Network
- Complexity
- Low
- Attack requirements
- None
- Privileges needed
- Low
- User interaction
- None
- Confidentiality
- High
- Integrity
- High
- Availability
- None
Raw vector
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/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
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-26978.md and follow it. Check whether this project is affected by CVE-2026-26978. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- 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