Local privilege escalation via writable executable or DLL

Privilege escalation in Valve Steam Client 1738026274 allows local users to execute code at higher privileges via a crafted executable or DLL. Insecure permissions allow a low-privileged local user to replace a Steam executable or DLL with attacker-controlled code that a higher-privileged user later launches. Exploitation requires local access and a subsequent launch or login by a higher-privileged user; the disclosed consequence is code execution at that user's privilege level.