CVE-2026-76834

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.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://b2evolution.net/news/2022/03/26/2022-update-eol
https://gist.github.com/axg11/3e29501c33f6e1e05ac2a00107afd64e
https://github.com/b2evolution/b2evolution
https://github.com/b2evolution/b2evolution/blob/7.2.5/htsrv/call_plugin.php#L49
https://github.com/b2evolution/b2evolution/blob/7.2.5/inc/_core/_param.funcs.php#L2860
https://github.com/b2evolution/b2evolution/commit/25c21cf9cc4261324001f9039509710b37ee2c4d
https://github.com/b2evolution/b2evolution/commit/335abf09bcea61717bd00bc1e3889f8100ebd1bb
https://github.com/b2evolution/b2evolution/commit/999b5ad1d59760d7e450ceb541f55432fc74cd27
https://www.vulncheck.com/advisories/b2evolution-cms-6.7.8-through-7.2.5-object-injection-via-negative-integer-array-key

Configurations

No configuration.

History

17 Sep 2026, 16:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-17 16:17

Updated : 2026-09-17 16:17

NVD link : CVE-2026-76834

Mitre link : CVE-2026-76834

CVE.ORG link : CVE-2026-76834

JSON object : View

Products Affected

No product.

CWE

CWE-502

Deserialization of Untrusted Data

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