Vulnerability · Published Jun 15, 2026 · Assigned by CERT-PL
CVE-2026-11860Insecure Deserialisation via Plaintext HTTP leading to Remote Code Execution in Quick.CMS
High 7.5
In plain English
A high-severity unsafe deserialization in Quick.CMS from OpenSolution. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 15% of all known vulnerabilities).
Official description
Quick.CMS deserializes user-controlled data received over plaintext HTTP without ensuring integrity or authenticity. This allows attackers to tamper with serialized payloads in transit and inject malicious objects. Because deserialization is performed without proper validation or class restrictions, crafted payloads can trigger dangerous magic methods (e.g., __wakeup() and __destruct()) and leverage gadget chains, resulting in arbitrary code execution. Exploitation is triggered automatically when an administrator accesses the admin panel. When successfully exploited, this vulnerability allows attackers to execute arbitrary code on the server via manipulated serialized data transmitted over an unprotected channel. This issue was mitigated by limiting the communication to HTTPS in a patch for version 6.8 published on 14.05.2026, deployments without this patch remain vulnerable.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| OpenSolution | Quick.CMS | 0 – through 6.8 |
Weakness: CWE-502, CWE-94 · Vector: CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L
References
- https://cert.pl/posts/2026/06/CVE-2026-11860/ third-party-advisory
- https://opensolution.org/ product