CVE-2026-66565: CWE-502 Deserialization of Untrusted Data in axiomthemes FC United
Description
CVE-2026-66565 is a critical vulnerability in axiomthemes FC United versions up to and including 1.1.1. It involves unauthenticated PHP Object Injection due to deserialization of untrusted data, classified under CWE-502. The vulnerability allows remote attackers to execute arbitrary code without authentication.
CVSS v3.1
Score 9.8critical
Affected software
axiomthemes
FC United
pkg:composer/axiomthemes/fc-unitedRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-66565) affects axiomthemes FC United versions <= 1.1.1 and is caused by unsafe deserialization of untrusted data leading to PHP Object Injection. The flaw allows unauthenticated attackers to inject malicious objects, potentially resulting in full system compromise. The CVSS 3.1 base score is 9.8, indicating critical severity with network attack vector, no privileges required, no user interaction, and high impact on confidentiality, integrity, and availability.
Potential Impact
Successful exploitation can lead to remote code execution with full impact on confidentiality, integrity, and availability of the affected system. Since no authentication is required, attackers can exploit this remotely without user interaction.
Mitigation Recommendations
No patch or official fix information is provided in the available data. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, restrict access to the affected application and monitor for suspicious activity related to PHP object injection.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- Patchstack
- Date Reserved
- 2026-07-27T13:59:48.657Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6aca96c12cdf04f6564a6049
Added to database: 10/10/2026, 19:49:21 UTC
Last enriched: 10/10/2026, 20:03:46 UTC
Last updated: 10/10/2026, 20:08:25 UTC
Views: 7
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