CVE-2026-11860: Quick.CMS deserializes user-controlled data received over plaintext HTTP without ensuring integrity or authenticity. This allows attackers to tamper w...

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.

Metrics

CVSS 4.0

7.5/10

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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

EPSS Probability

0.24%

14.4th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

References

Timeline

Published: Jun 15, 2026
Last Modified: Jun 17, 2026
Status: Deferred

Frequently Asked Questions

What is CVE-2026-11860?

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.

How severe is CVE-2026-11860?

CVE-2026-11860 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 0.24% probability of exploitation in the next 30 days.

How do I fix CVE-2026-11860?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.