No Patch for New PhantomRPC Privilege Escalation Technique in Windows
PhantomRPC is a local privilege escalation vulnerability in Windows RPC that allows an attacker to impersonate privileged services by deploying a fake RPC server. This architectural weakness enables escalation to System privileges by intercepting RPC requests intended for legitimate services. The issue affects multiple Windows versions and exploits legitimate Windows impersonation mechanisms. Kaspersky reported the vulnerability, and Microsoft has classified it as moderate severity, stating it does not require immediate remediation. No official patch is currently available. Exploitation requires compromising a privileged service and setting up a fake RPC server to intercept and impersonate RPC calls. Several attack paths have been identified involving services running under Network Service and Local Service accounts. The vulnerability increases the attack surface for local privilege escalation but requires specific conditions to exploit.
AI Analysis
Technical Summary
PhantomRPC is a local privilege escalation vulnerability in Windows Remote Procedure Call (RPC) due to an architectural weakness where the RPC runtime does not verify the legitimacy of RPC servers. Attackers who compromise a privileged service can deploy a fake RPC server exposing the same endpoints as legitimate services, intercept RPC requests, and impersonate the targeted service to escalate privileges to System. The vulnerability affects multiple Windows services running under Network Service and Local Service accounts, including TermService, DHCP Client, and Windows Time service. Exploitation involves forcing high-privileged services to make RPC calls to the fake server, which then impersonates the caller's security context. Kaspersky disclosed the issue in September 2025, and Microsoft has classified it as moderate severity, indicating no immediate remediation is required. No patch or official fix has been released as of the publication date.
Potential Impact
Successful exploitation of PhantomRPC allows an attacker with local access and the ability to compromise a privileged service to escalate privileges to the System level. This can lead to full control over the affected Windows system. The vulnerability leverages legitimate Windows impersonation mechanisms and RPC communication, increasing the attack surface for local privilege escalation. However, exploitation requires specific conditions, including the compromise of privileged services and deployment of a fake RPC server. Microsoft currently classifies the vulnerability as moderate severity and does not consider immediate remediation necessary.
Mitigation Recommendations
No official patch or fix is currently available for PhantomRPC. Microsoft has classified the vulnerability as moderate severity and has indicated that immediate remediation is not required. Organizations should monitor vendor advisories for updates. Since exploitation requires compromising privileged services and deploying fake RPC servers, restricting local access and maintaining strong service account security may reduce risk. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance.
No Patch for New PhantomRPC Privilege Escalation Technique in Windows
Description
PhantomRPC is a local privilege escalation vulnerability in Windows RPC that allows an attacker to impersonate privileged services by deploying a fake RPC server. This architectural weakness enables escalation to System privileges by intercepting RPC requests intended for legitimate services. The issue affects multiple Windows versions and exploits legitimate Windows impersonation mechanisms. Kaspersky reported the vulnerability, and Microsoft has classified it as moderate severity, stating it does not require immediate remediation. No official patch is currently available. Exploitation requires compromising a privileged service and setting up a fake RPC server to intercept and impersonate RPC calls. Several attack paths have been identified involving services running under Network Service and Local Service accounts. The vulnerability increases the attack surface for local privilege escalation but requires specific conditions to exploit.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
PhantomRPC is a local privilege escalation vulnerability in Windows Remote Procedure Call (RPC) due to an architectural weakness where the RPC runtime does not verify the legitimacy of RPC servers. Attackers who compromise a privileged service can deploy a fake RPC server exposing the same endpoints as legitimate services, intercept RPC requests, and impersonate the targeted service to escalate privileges to System. The vulnerability affects multiple Windows services running under Network Service and Local Service accounts, including TermService, DHCP Client, and Windows Time service. Exploitation involves forcing high-privileged services to make RPC calls to the fake server, which then impersonates the caller's security context. Kaspersky disclosed the issue in September 2025, and Microsoft has classified it as moderate severity, indicating no immediate remediation is required. No patch or official fix has been released as of the publication date.
Potential Impact
Successful exploitation of PhantomRPC allows an attacker with local access and the ability to compromise a privileged service to escalate privileges to the System level. This can lead to full control over the affected Windows system. The vulnerability leverages legitimate Windows impersonation mechanisms and RPC communication, increasing the attack surface for local privilege escalation. However, exploitation requires specific conditions, including the compromise of privileged services and deployment of a fake RPC server. Microsoft currently classifies the vulnerability as moderate severity and does not consider immediate remediation necessary.
Mitigation Recommendations
No official patch or fix is currently available for PhantomRPC. Microsoft has classified the vulnerability as moderate severity and has indicated that immediate remediation is not required. Organizations should monitor vendor advisories for updates. Since exploitation requires compromising privileged services and deploying fake RPC servers, restricting local access and maintaining strong service account security may reduce risk. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance.
Technical Details
- Article Source
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Threat ID: 69f09bb5cbff5d861003a307
Added to database: 4/28/2026, 11:36:21 AM
Last enriched: 4/28/2026, 11:36:30 AM
Last updated: 4/28/2026, 12:49:00 PM
Views: 7
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