A critical elevation-of-privilege vulnerability in the Windows Remote Access Connection Manager (RasMan) can be weaponized by a local attacker to execute arbitrary code with System privileges. The flaw centers on RasMan’s handling of RPC endpoints: if an attacker can register the trusted endpoint before RasMan does, privileged services may later communicate with the attacker’s process instead of the real service, enabling arbitrary command execution as SYSTEM.
The exploit chain reported against this issue is notable because it combines two conditions. The primary, patched flaw (CVE-2025-59230) is the endpoint-registration race that enables privilege escalation when the attacker controls the endpoint first. In practice, however, RasMan normally starts at boot and registers that endpoint early, so the race window is small. To overcome this, researchers observed a second, previously undocumented crash vector: a logic error that can be triggered to intentionally crash RasMan, stop the service, and free the RPC endpoint so the attacker can register it and complete the exploitation chain.
Technical summary
RasMan registers an RPC endpoint that other privileged services trust. When that registration can be preempted, privileged inter-process communications may be redirected to an attacker-controlled process. The secondary crash vector involves a circular linked-list traversal where NULL pointers are not handled correctly, producing a memory-access violation that can crash RasMan and create the opportunity for endpoint re-registration. Because the two issues are used together in the observed exploit chain, full exploitation requires both the race-condition behavior and the ability to reliably stop the service first.
Mitigations
Microsoft issued official patches addressing the elevation-of-privilege weakness (CVE-2025-59230) as part of the October 2025 security updates. At the time the issue was publicly described, the crash-trigger used to facilitate the attack had not been addressed in Microsoft’s official updates; a third party released micropatches targeting that crash vector across supported platforms. Administrators should apply the October 2025 updates immediately and evaluate whether supplemental mitigations or third-party micropatches are necessary in environments where the crash vector would materially increase risk.
Recommendations
Prioritize deployment of the vendor-supplied updates for CVE-2025-59230 across endpoints and servers. Where rapid patching is constrained, consider compensating controls that reduce the risk of local, unprivileged users being able to execute code (for example, strict local user privilege management, application control, and endpoint monitoring for unexpected service crashes and suspicious RPC registrations). Log and alert on unusual RasMan start/stop activity and on processes that register RPC endpoints typically owned by system services.
Final note
The primary flaw was addressable through standard vendor patching, but the presence of a companion crash vector shows the necessity of defense in depth, combining timely patching, principle-of-least-privilege controls, and robust monitoring. Automated or out-of-cycle mitigations are valuable when attack chains rely on secondary, unpatched behaviors; however, long-term risk is best reduced by eliminating the underlying code defects in the trusted service.
Mourad Maacha 
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