CVE Catalog

CVE-2026-76834

HighCVSS 8.1
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Elevated risk
0.85%

57th percentile - higher than 57% of all known CVEs

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.

Risk Assessment

An unauthenticated attacker can instantiate arbitrary PHP objects with attacker-controlled properties, potentially leading to remote code execution when POP gadgets are available. The risk is critical for publicly accessible b2evolution installations.

Recommendation

Upgrade b2evolution CMS to a version containing the complete serialized-array validation fix, or restrict access to htsrv/call_plugin.php to trusted sources.

Related vulnerabilities

Original NVD description (English source)

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.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS