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CVE-2026-7888

CVE-2026-7888 · Concrete CMS below 9.5.3 is vulnerable to PHP Object Injection via unserialize() calls in the Workflow, Form block, and File/Set components that lack the allowed_classes restriction.

This page contains facts from public vulnerability sources. Check the original advisory before updating.

Concrete CMS below 9.5.3 is vulnerable to PHP Object Injection via unserialize() calls in the Workflow, Form block, and File/Set components that lack the allowed_classes restriction. The Form block and File/Set sinks were addressed in 9.5.2; the Workflow component sinks were addressed in 9.5.3. An unauthenticated attacker may trigger arbitrary PHP object instantiation if a malicious serialized payload has been placed in the database. Thanks XananasX7 and Sanjorn Keeratirungsan (dizconnect) for independently reporting the original components, and sh4d0byss for reporting the Workflow component wasn't fixed in 9.5.2. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 8.4 with vector CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/ VC:H/VI:H/VA:H/SC:N/SI:N/SA:N.

CVSS 8.4 · High · EPSS 0.2% · Fix available

Published
Updated

Stack: php

Affected products and versions

  • concrete cms

    Versions
    • ≥ 5.0, ≤ 9.5.2: Affected (git)

    No fix published

  • concrete5/concrete5 Packagist

    Versions
    • 8.0
    • 8.0.1
    • 8.0.2
    • 8.0.3
    • 8.1.0
    • 8.2.0
    • 8.2.0RC2
    • 8.2.1
    • 8.3.0
    • 8.3.1
    • 8.3.2
    • 8.4.0
    • 8.4.0RC3
    • 8.4.0RC4
    • 8.4.1
    • 8.4.2
    • 8.4.3
    • 8.4.4
    • 8.4.5
    • 8.5.0
    • 8.5.0RC1
    • 8.5.0RC2
    • 8.5.1
    • 8.5.10
    • 8.5.11
    • 8.5.12
    • 8.5.13
    • 8.5.14
    • 8.5.15
    • 8.5.16
    • 8.5.17
    • 8.5.18
    • 8.5.19
    • 8.5.2
    • 8.5.20
    • 8.5.21
    • 8.5.3
    • 8.5.4
    • 8.5.5
    • 8.5.6
    • 8.5.6RC1
    • 8.5.7
    • 8.5.8
    • 8.5.9
    • 9.0.0
    • 9.0.0RC1
    • 9.0.0RC3
    • 9.0.0RC4
    • 9.0.1
    • 9.0.2
    • 9.1.0
    • 9.1.1
    • 9.1.2
    • 9.1.3
    • 9.2.0
    • 9.2.0RC2
    • 9.2.1
    • 9.2.2
    • 9.2.3
    • 9.2.4
    • 9.2.5
    • 9.2.6
    • 9.2.7
    • 9.2.8
    • 9.2.9
    • 9.3.0
    • 9.3.1
    • 9.3.2
    • 9.3.3
    • 9.3.4
    • 9.3.5
    • 9.3.6
    • 9.3.7
    • 9.3.8
    • 9.3.9
    • 9.4.0
    • 9.4.0RC1
    • 9.4.0RC2
    • 9.4.1
    • 9.4.2
    • 9.4.3
    • 9.4.4
    • 9.4.5
    • 9.4.6
    • 9.4.7
    • 9.4.8
    • 9.5.0
    • 9.5.0RC1
    • 9.5.0RC2
    • 9.5.1
    Affected ranges
    • ECOSYSTEM: < 9.5.2

    Update to 9.5.2

Original sources

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