CVE-2015-2387: Microsoft ATM Font Driver Privilege Escalation Vulnerability

CVE-2015-2387 is a privilege-escalation vulnerability in the Adobe Type Manager Font Driver component (ATMFD.DLL) used by Microsoft Windows Server. A local user who can run a crafted application may be able to obtain higher privileges on the system. Because font-driver code often runs in a privileged context, successful abuse can turn a limited foothold into full administrative control, which is why defenders treat this class of issue as high priority once an attacker already has local access.

Public detail is limited to the CISA summary and the stated weakness; exact affected builds, scoring, and exploit mechanics must be confirmed against the vendor advisory. Known ransomware use is not documented for this CVE.

How it works

The weakness is classified as CWE-264 (Permissions, Privileges, and Access Controls). In plain terms, the Adobe Type Manager Font Driver does not adequately enforce the privilege boundary between an unprivileged process and the privileged code path that handles font-related operations inside ATMFD.DLL.

An attacker who already has the ability to execute code as a standard user supplies a crafted application that interacts with the vulnerable driver. Because the driver runs with elevated rights, a successful trigger can allow the attacker’s code to run with those higher privileges. No remote, unauthenticated vector is described in the available facts; the attack requires local execution of the malicious application. Specifics of the trigger or memory corruption pattern are not provided here and should be taken only from the vendor advisory.

Am I affected? How to find it in your systems

The component sits inside Microsoft Windows Server installations that include the Adobe Type Manager Font Driver (ATMFD.DLL). It is typically present on systems that process fonts or that have not had the driver disabled or removed by policy.

• Inventory Windows Server hosts (physical, virtual, and cloud images) and confirm the presence of ATMFD.DLL under the system directory.
• Compare installed OS builds and security-update levels against the list of fixed versions published in the Microsoft advisory for CVE-2015-2387; do not rely on version guesses.
• Check group-policy or hardening baselines that may already disable the ATM font driver; absence of the DLL or a disabled service/driver entry reduces exposure.
• Review endpoint-detection and process-creation logs for unusual local applications that load or interact with ATMFD.DLL, especially from non-administrative user contexts. Telemetry showing sudden privilege elevation after font-related activity can be a post-exploitation indicator, though it is not unique to this CVE.

If your asset-management or vulnerability-scanning tools already map Microsoft security bulletins, use them to flag hosts missing the corresponding update. Confirm every finding against the official vendor advisory before declaring a system clean or affected.

How to remediate

The primary action is to apply the security update that Microsoft released for this vulnerability, following the vendor’s installation and reboot guidance. CISA’s required action is simply: apply updates per vendor instructions.

• Deploy the patch through your normal Windows Update, WSUS, SCCM/ConfigMgr, or other enterprise patching pipeline.
• Verify successful installation by checking the update history and the file version of ATMFD.DLL against the advisory.
• After patching, re-enable any temporary hardening only if it is still required by policy; otherwise return systems to the supported, patched configuration.
• For long-term hardening of this class of issue, keep font-parsing components updated, restrict which users can install or load arbitrary fonts/applications, and maintain least-privilege execution so that a local compromise does not immediately yield SYSTEM-level rights.

If you can't patch immediately

Until the vendor update can be installed, reduce the attack surface with compensating controls appropriate to a local privilege-escalation flaw in a font driver:

• Segment high-value servers so that only administrators and necessary management tools can reach them; limit interactive logon rights for standard users.
• Where operationally feasible, disable or remove the Adobe Type Manager Font Driver if your environment does not require it; test thoroughly first.
• Apply application-allow-listing so that only approved binaries can execute; this blocks many crafted applications used for local escalation.
• Increase monitoring on process creation, privilege-change events, and loads of ATMFD.DLL; alert on anomalies from non-admin accounts.
• Virtual patching via host-based intrusion-prevention or EDR rules that block known exploitation patterns can provide temporary coverage, but only after validating the rules against the vendor’s description of the issue.

These measures lower risk; they do not replace the official patch.

If your data may have been exposed

Actively exploited local privilege-escalation vulnerabilities are commonly used after an initial foothold to move laterally, dump credentials, or stage further payloads, which can lead to data exposure or ransomware. Known ransomware use is not documented for CVE-2015-2387, yet any successful elevation still warrants investigation of the host and connected accounts. If you believe systems were compromised, follow your incident-response process, isolate affected machines, and rotate credentials. You can also run a free exposure scan of your email addresses to check whether they appear in known breach data sets and take appropriate account-protection steps.