Synopsis
Local Privilege Escalation
This is due to the PsExec service component (PsExecSvc.exe) and how it uses its "\\.\pipe\PSEXESVC" named pipe. A low privileged attacker is able to create a named pipe with the same name before PsExecSvc starts on the machine. Once PsExecSvc starts and calls "CreateNamedPipe," a handle of the existing named pipe is obtained which still has the ACL's from the low privileged attacker, thus allowing the low privileged attacker to read/write to this pipe being used by PsExecSvc (which should be Administrator/System only). In this case, a low privileged attacker can execute any process locally as SYSTEM through this pipe. This vulnerability can be exploited on the target machine in either local or remote PsExec usage scenarios.
Solution
There is no known solution or mitigation for this issue.Proof of Concept
Disclosure Timeline
All information within TRA advisories is provided “as is”, without warranty of any kind, including the implied warranties of merchantability and fitness for a particular purpose, and with no guarantee of completeness, accuracy, or timeliness. Individuals and organizations are responsible for assessing the impact of any actual or potential security vulnerability.
Tenable takes product security very seriously. If you believe you have found a vulnerability in one of our products, we ask that you please work with us to quickly resolve it in order to protect customers. Tenable believes in responding quickly to such reports, maintaining communication with researchers, and providing a solution in short order.
For more details on submitting vulnerability information, please see our Vulnerability Reporting Guidelines page.
If you have questions or corrections about this advisory, please email [email protected]
Contact our sales team