CVE-2026-76834
b2evolution CMS 6.7.8 through 7.2.5 Object Injection via Negative Integer Array Key
CVSS Score
8.1
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-502 |
| Vendor | b2evolution |
| Product | b2evolution cms |
| Published | Sep 17, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H Attack Vector
Network
Attack Complexity
High
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
Affected Versions
b2evolution / b2evolution CMS
6.7.8 ≤ 7.2.5
References
gist.github.com: https://gist.github.com/axg11/3e29501c33f6e1e05ac2a00107afd64e github.com: https://github.com/b2evolution/b2evolution/blob/7.2.5/inc/_core/_param.funcs.php#L2860 github.com: https://github.com/b2evolution/b2evolution/blob/7.2.5/htsrv/call_plugin.php#L49 github.com: https://github.com/b2evolution/b2evolution/commit/25c21cf9cc4261324001f9039509710b37ee2c4d github.com: https://github.com/b2evolution/b2evolution/commit/999b5ad1d59760d7e450ceb541f55432fc74cd27 github.com: https://github.com/b2evolution/b2evolution/commit/335abf09bcea61717bd00bc1e3889f8100ebd1bb b2evolution.net: https://b2evolution.net/news/2022/03/26/2022-update-eol github.com: https://github.com/b2evolution/b2evolution vulncheck.com: https://www.vulncheck.com/advisories/b2evolution-cms-6.7.8-through-7.2.5-object-injection-via-negative-integer-array-key
Credits
Adrian Gaitan VulnCheck