CVE-2026-26978Network attack vector

Authenticated code execution via unsafe manifest deserialization

Published May 18, 2026 · Updated May 18, 2026

Unsafe deserialization in FreePBX backup before 16.0.71 and 17.0.6 allows remote authenticated users to execute code during restore. BackupSplFileInfo::getMetadata reads an extracted manifest and passes it to unserialize() without validation, integrity checks, or class restrictions. Access to the restore workflow or write access to backup files is required, and successful exploitation runs code as the web server user.

CVSS severity8.6
High
EPSS probability0.90%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Unsafe deserialization in FreePBX backup before 16.0.71 and 17.0.6 allows remote authenticated users to execute code during restore. BackupSplFileInfo::getMetadata reads an extracted manifest and passes it to unserialize() without validation, integrity checks, or class restrictions. Access to the restore workflow or write access to backup files is required, and successful exploitation runs code as the web server user.

The record

CVE
CVE-2026-26978
Published
May 18, 2026
Updated
May 18, 2026
Vendor
FreePBX
Product
Backup & Restore
Classifications
CWE-502, T1190
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. May 18, 2026CVE publishedPublication date reported by the CVE source.
  2. May 18, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 16.0.71
  2. Affected versionversion=>= 17.0.0, < 17.0.6

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

FreePBX · Backup & Restoreversion=< 16.0.71; version=>= 17.0.0, < 17.0.6

Published CVSS scores

8.6GitHubCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-502Deserialization of Untrusted Data
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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