CVE-2026-26978

Year
2026
Published
May 18, 2026
Known Affected Devices
0
CVSS Score
N/A

What is 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.

FAQ

How severe is CVE-2026-26978?

CVE-2026-26978 has a CVSS score of N/A/10, rated as Unknown. Review the affected products list and apply vendor patches.

What does the CVSS score mean for CVE-2026-26978?

CVSS (Common Vulnerability Scoring System) rates vulnerability severity from 0.0 to 10.0. CVE-2026-26978 scores N/A/10 (Unknown). Scores 9.0–10.0 are Critical, 7.0–8.9 are High, 4.0–6.9 are Medium, and below 4.0 are Low.

Which devices are affected by CVE-2026-26978?

The list of devices confirmed to be affected by CVE-2026-26978 is shown in the "Affected Devices" section above. Check your firmware version against the vendor security advisory and apply the latest patch.

How do I fix or mitigate CVE-2026-26978?

Apply the latest firmware or software update from the vendor. Check the References section above for official advisories and patch notes. If no patch is available, consider disabling the affected feature or isolating the device from untrusted networks.