{"id":"CVE-2026-70554","published":"2026-08-04T21:16:38.613","lastModified":"2026-08-05T15:17:13.783","description":"MaxSite CMS contains a PHP object injection vulnerability that allows unauthenticated attackers to execute arbitrary code by passing attacker-controlled serialized data in the maxsite_comuser cookie directly to unserialize() without validation or class allowlisting. Attackers can craft a malicious serialized PHP object payload delivered in a single HTTP request to trigger magic methods during object graph reconstruction, enabling property-oriented programming attacks or remote code execution via available gadget chains such as those targeting SoapClient or Imagick extensions.","cvssScore":9.8,"cvssSeverity":"CRITICAL","cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","cwes":["CWE-502"],"vendors":[],"products":[],"references":[{"url":"https://github.com/maxsite/cms","tags":[]},{"url":"https://max-3000.com/page/maxsite-cms-109-6","tags":[]},{"url":"https://www.vulncheck.com/advisories/maxsite-cms-unauthenticated-php-object-injection-via-maxsite-comuser-cookie","tags":[]}],"exploitRefs":[{"url":"https://github.com/maxsite/cms","tags":[]}],"hasPoc":true,"ai":{"summary":"The flaw is a PHP object injection vulnerability in MaxSite CMS that allows unauthenticated attackers to execute arbitrary code by passing malicious serialized data through the maxsite_comuser cookie. This matters because it can lead to full system compromise without authentication.","exploitability":"Exploitation requires crafting a specific malicious payload and sending it via an HTTP request, which is moderately difficult but feasible given public exploit references.","blast_radius":"If exploited, this could result in complete control over the affected server or network, with potential impact ranging from data theft to full system compromise.","remediation":"Update MaxSite CMS to a patched version immediately and validate all user inputs, especially those involving serialized data.","tags":["rce","web","cms","php","unauth"],"model":"qwen2.5:7b-instruct","analyzedAt":"2026-08-11T06:42:41.839Z"}}