Description (en)
0day Rubbish Research Team is publicly disclosing a vulnerability in Stimulsoft Server 2026.3.1 (Stimulsoft). The
research is published and a proof-of-concept is available.
Pre-authentication SYSTEM RCE (CVSS 9.8, pre-authentication)
A default-configuration defect chain combines into a complete unauthenticated RCE. The /1/signup endpoint is open by
default with email activation disabled, so an anonymous attacker registers and immediately receives a Supervisor
account. The Supervisor uploads a .mrt report template containing an embedded C# script. PUT
/1/reporttemplates/<id>/run triggers the report-script engine, which compiles the script with CSharpCodeProvider in
full trust (no AppDomain isolation, no CAS sandbox, no class allowlist) and instantiates the report class, executing
the attacker-controlled constructor. The report task runs in the backend service process Stimulsoft.Server.Agent.exe as
NT AUTHORITY\SYSTEM. No credentials, no SMTP, no administrator action, and no non-default configuration are required.
Impact: Full system takeover; the report task executes in the backend service process running as NT AUTHORITY\SYSTEM,
giving arbitrary code execution with the highest Windows privilege.
Advisory: https://0day-rubbish.com/blog/stimulsoft-server-unauth-report-script-rce
PoC and full analysis: https://github.com/Exploit-Garbage/0day-Rubbish
--
0day Rubbish Research Team
https://0day-rubbish.com
_______________________________________________
Sent through the Full Disclosure mailing list
https://nmap.org/mailman/listinfo/fulldisclosure
Web Archives & RSS: https://seclists.org/fulldisclosure/
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