CVE-2026-70554: MaxSite CMS Unauthenticated PHP Object Injection via maxsite_comuser Cookie
MaxSite · MaxSite CMS
Vendor fix available · Affected: MaxSite CMS · Exploitation: possible (1 to 10%)
Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.
Higher than 69% of scored CVEs
DescriptionCVE.org
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.
Affected products1
From the CVE record. A product or version that is not listed is unknown, not unaffected.
- MaxSite · MaxSite CMSfrom 0.78 up to and including 109.5
On the Atlas
Every published CVE is on the CyberSIXT Atlas, grouped by weakness, vendor and month.
- Exploitation
- Possible (1 to 10%). EPSS between 1% and 10%.
- CISA KEV
- Not listed
- Public check
- No public nuclei template
- Vendor
- MaxSite
- Published
- August 2026
CoverageNo articles yet
No CyberSIXT article names CVE-2026-70554 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.