CVE-2018-8440: Windows ALPC local privilege escalation

Automated analysis

Generated by VULONE's analysis model from the NVD record, CISA KEV and EPSS data on 17 September 2026. Confidence: high.

high priorityThe flaw is a high-severity local privilege escalation with confirmed in-the-wild exploitation and ransomware use, though it requires an existing foothold rather than remote access.

What it is

Windows improperly handles calls to the Advanced Local Procedure Call (ALPC) interface, allowing a local user to elevate privileges. The flaw affects a broad set of Windows client and server releases, and it has been exploited in the wild, making it a serious post-compromise escalation path.

Impact

An attacker who already has a foothold on a host can gain elevated privileges, typically SYSTEM, and then move laterally or disable defenses. CISA notes known use in ransomware campaigns, so escalation can feed directly into destructive or encrypting activity.

Attack surface

The vector is local (AV:L) with low privileges required (PR:L) and no user interaction (UI:N), so the attacker must already be able to run code on the target machine. It is not remotely reachable and does not depend on tricking a user.

Exploitation

CVE-2018-8440 is listed in CISA KEV with known ransomware campaign use, and EPSS shows a 30-day probability of roughly 18 percent (97th percentile). Reference tags include an exploit write-up, confirming public exploit material exists.

What to do

• Apply the Microsoft security update for CVE-2018-8440 to all affected Windows versions, prioritizing internet-facing and high-value hosts.
• Retire or isolate unsupported platforms such as Windows 7, Windows Server 2008 and 2008 R2 that cannot receive current patches.
• Enforce least privilege so standard users cannot run arbitrary code, and restrict local admin rights to reduce the value of an escalation primitive.
• Monitor for and block known exploit tooling and post-exploitation behavior associated with this ALPC flaw.
• Where patching is delayed, consider third-party micropatch options referenced in the advisory as a temporary control.

Detection

• Alert on unexpected processes spawning with SYSTEM or high-integrity tokens from user-writable directories.
• Monitor ALPC-related API activity and unusual handle operations from non-privileged processes.
• Hunt for known exploit binaries or scripts tied to CVE-2018-8440 by hash and filename.
• Correlate local privilege escalation events with subsequent credential dumping, service creation or ransomware deployment activity.

This assessment is produced automatically and is not human-reviewed. Verify against the vendor advisory before acting on it.