CVE-2026-76834 (GCVE-0-2026-76834)
Vulnerability from cvelistv5
Published
2026-09-17 15:16
Modified
2026-09-18 18:04
Severity ?
9.2 (Critical) - CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
8.1 (High) - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE
  • CWE-502 - Deserialization of Untrusted Data
Summary
b2evolution CMS versions 6.7.8 through 7.2.5 contain an incomplete fix for CVE-2016-8901 where the serialized-array object check in param_check_serialized_array() fails to reject payloads with negative integer array keys. Unauthenticated attackers can submit crafted serialized PHP objects via POST requests to htsrv/call_plugin.php that bypass validation and reach unserialize(), instantiating arbitrary PHP objects with attacker-chosen properties that may enable code execution if suitable POP gadget chains exist.
References
Impacted products
Vendor Product Version
b2evolution b2evolution CMS Version: 6.7.8   ≤ 7.2.5
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