{"id":"CVE-2026-76834","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-76834","generatedAt":"2026-09-20T10:52:18.326Z","title":"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…","description":"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.","published":"2026-09-17T16:17:42.000Z","lastModified":"2026-09-18T18:17:14.000Z","status":"Received","sourceIdentifier":"disclosure@vulncheck.com","cvss":{"version":"4.0","score":9.2,"severity":"CRITICAL","vector":"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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M"},"cwe":["CWE-502"],"affected":[],"epss":{"score":0.00847,"percentile":0.56505,"date":"2026-09-19","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.85%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://b2evolution.net/news/2022/03/26/2022-update-eol","source":"disclosure@vulncheck.com"},{"url":"https://gist.github.com/axg11/3e29501c33f6e1e05ac2a00107afd64e","source":"disclosure@vulncheck.com"},{"url":"https://github.com/b2evolution/b2evolution","source":"disclosure@vulncheck.com"},{"url":"https://github.com/b2evolution/b2evolution/blob/7.2.5/htsrv/call_plugin.php#L49","source":"disclosure@vulncheck.com"},{"url":"https://github.com/b2evolution/b2evolution/blob/7.2.5/inc/_core/_param.funcs.php#L2860","source":"disclosure@vulncheck.com"},{"url":"https://github.com/b2evolution/b2evolution/commit/25c21cf9cc4261324001f9039509710b37ee2c4d","source":"disclosure@vulncheck.com"},{"url":"https://github.com/b2evolution/b2evolution/commit/335abf09bcea61717bd00bc1e3889f8100ebd1bb","source":"disclosure@vulncheck.com"},{"url":"https://github.com/b2evolution/b2evolution/commit/999b5ad1d59760d7e450ceb541f55432fc74cd27","source":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/b2evolution-cms-6.7.8-through-7.2.5-object-injection-via-negative-integer-array-key","source":"disclosure@vulncheck.com"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-76834","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}