CVE-2026-7888

Arbitrary object instantiation via unrestricted deserialization

Published Jun 3, 2026 · Updated Jun 3, 2026

PHP object injection in Concrete CMS before 9.5.2 allows attackers to instantiate arbitrary PHP objects from stored database payloads. Workflow, Form block, and File/Set code passes serialized database values to unserialize() without restricting allowed_classes. Exploitation requires a malicious serialized payload already stored in the database; published material identifies no direct network path or specific gadget-chain outcome.

CVSS severity8.4
High
EPSS probability0.15%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

PHP object injection in Concrete CMS before 9.5.2 allows attackers to instantiate arbitrary PHP objects from stored database payloads. Workflow, Form block, and File/Set code passes serialized database values to unserialize() without restricting allowed_classes. Exploitation requires a malicious serialized payload already stored in the database; published material identifies no direct network path or specific gadget-chain outcome.

The record

CVE
CVE-2026-7888
Published
Jun 3, 2026
Updated
Jun 3, 2026
Vendor
Concrete CMS
Product
Concrete CMS
Classifications
CWE-502, CAPEC-586
Attack vector
local
Privileges
admin

Timeline

How it unfolded

  1. Jun 3, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 3, 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=5.0 <9.5.2

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

Concrete CMS · Concrete CMSversion=5.0 <9.5.2

Published CVSS scores

8.4Concrete CMSCVSS: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 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.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-502Deserialization of Untrusted Data
CAPEC-586Object Injection

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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