CVE-2026-71981
Cypht < 2.12.2 PHP Object Injection RCE via back_query Parameter
CVSS Score
8.8
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-502 |
| Vendor | cypht-org |
| Product | cypht |
| Published | Sep 1, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
Affected Versions
cypht-org / cypht
0 < 2.12.2
References
github.com: https://github.com/cypht-org/cypht/releases/tag/v2.12.2 github.com: https://github.com/cypht-org/cypht/pull/2073 github.com: https://github.com/cypht-org/cypht/commit/e4aa2f34e33f9328e8c93514cc3966fc3d99925e vulncheck.com: https://www.vulncheck.com/advisories/cypht-php-object-injection-rce-via-back-query-parameter
Credits
Adam Młynarczyk