Cypht < 2.12.2 PHP Object Injection RCE via back_query Parameter
41Vexday Risk Score
No sign of exploitation. It has a public proof of concept.
ssvc Attendcvss 8.7epss 1.0%
from disclosure to weapon1 days
Published on NVDSep 1
1st PoC+1d
exploitation probability
1.0%top 40% of all CVEs
observed exploitation
nono source reports it
1 public exploit(s)
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:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Affected products
cypht-org · cyphtpublic PoCs found — 1
githubgithub.com/lyn4r/CVE-2026-71981★ 0⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.