CVE-2026-71981

Cypht before 2.12.2 contains a PHP object injection vulnerability that allows authenticated attackers to execute arbitrary operating system commands by supplying a crafted PHP object graph in the back_query GET parameter of the logout handler. Attackers can pass a base64-encoded serialized payload through this parameter, which is decoded and passed directly to unserialize() without an allow-list, signature check, or type restriction, enabling gadget-chain exploitation to achieve remote code execution as the web server process.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/cypht-org/cypht/commit/e4aa2f34e33f9328e8c93514cc3966fc3d99925e
https://github.com/cypht-org/cypht/pull/2073
https://github.com/cypht-org/cypht/releases/tag/v2.12.2
https://www.vulncheck.com/advisories/cypht-php-object-injection-rce-via-back-query-parameter

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-01 21:18

Updated : 2026-09-08 20:18

NVD link : CVE-2026-71981

Mitre link : CVE-2026-71981

CVE.ORG link : CVE-2026-71981

JSON object : View

Products Affected

No product.

CWE

CWE-502

Deserialization of Untrusted Data

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