What products are affected by CVE-2009-1537?

CVE-2009-1537 affects Microsoft DirectX. Refer to the vendor advisory and NVD record for affected versions.

What is the EPSS score for CVE-2009-1537?

CVE-2009-1537 has an EPSS score of 53.0%, placing it in the 98th percentile. This means it has a 53.0% probability of being exploited in the next 30 days, higher than 98% of all known vulnerabilities. EPSS (Exploit Prediction Scoring System) is maintained by FIRST and uses real-world threat data to estimate exploitation likelihood.

Actively Exploited — CISA KEV

CVE-2009-1537: Microsoft DirectX High-Severity Vulnerability

Severity: High | CVSS 3.1: 8.8 | Published: 2009-05-29 | KEV Added: 2026-05-20

What is CVE-2009-1537?

Unspecified vulnerability in the QuickTime Movie Parser Filter in quartz.dll in DirectShow in Microsoft DirectX 7.0 through 9.0c on Windows 2000 SP4, Windows XP SP2 and SP3, and Windows Server 2003 SP2 allows remote attackers to execute arbitrary code via a crafted QuickTime media file, as exploited in the wild in May 2009, aka "DirectX NULL Byte Overwrite Vulnerability."

Technical Analysis

Weakness Classification

This vulnerability is classified as CWE-158.

Attack Vector Breakdown

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: Required
Scope: Unchanged
Confidentiality: High
Integrity: High
Availability: High

Impact Analysis

This vulnerability is exploitable over the network, meaning any system reachable via the internet or internal network is potentially at risk without physical access. The attack complexity is low, meaning exploitation does not depend on specialized conditions or race windows. Successful exploitation can result in full confidentiality breach (complete data disclosure), complete integrity compromise (data modification or code execution), total availability loss (denial of service).

Exploitation Probability (EPSS): 53.0% chance of exploitation in the next 30 days (98th percentile). This places the vulnerability in the highest risk tier — immediate action is critical.

Is CVE-2009-1537 being exploited?

Yes. CVE-2009-1537 is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, restricted to CVEs with confirmed active exploitation in the wild. CISA added this vulnerability on 2026-05-20. Inclusion in KEV triggers the patching mandate under BOD 22-01 for U.S. federal civilian agencies, with a remediation deadline of 2026-06-03.

How to fix CVE-2009-1537

Apply the latest security update via Windows Update, WSUS, or Microsoft Update Catalog. For enterprise environments, use SCCM/Intune for managed deployment. If the patch cannot be applied immediately, check the MSRC advisory for workarounds such as registry-based mitigations or disabling affected features. Check the Microsoft Security Response Center page for the specific patch or update. CISA's Known Exploited Vulnerabilities catalog requires U.S. federal agencies to remediate this vulnerability by the due date shown below under Binding Operational Directive 22-01. Private organizations should treat KEV entries as priority-one patches because active exploitation has been confirmed in the wild.

Related Vulnerabilities

Other actively exploited vulnerabilities affecting DirectX or sharing the same weakness (CWE-158):

CVE-2008-4250 (Critical 9.8) [same vendor] — The Server service in Microsoft Windows 2000 SP4, XP SP2 and SP3, Server 2003…
CVE-2010-0249 (High 8.8) [same vendor] — Use-after-free vulnerability in Microsoft Internet Explorer 6, 6 SP1, 7, and 8…
CVE-2010-0806 (High 8.8) [same vendor] — Use-after-free vulnerability in the Peer Objects component (aka iepeers.dll)…
CVE-2026-41091 (High 7.8) [same vendor] — Improper link resolution before file access ('link following') in Microsoft…
CVE-2026-45498 (Medium 4.0) [same vendor] — Microsoft Defender Denial of Service Vulnerability

Frequently asked questions

Is CVE-2009-1537 critical?

CVE-2009-1537 has a CVSS 3.1 base score of 8.8 — High severity. It should be treated as a priority patch, especially given the active exploitation confirmed by CISA.

Is CVE-2009-1537 being actively exploited?

Yes — CISA added CVE-2009-1537 to the Known Exploited Vulnerabilities catalog on 2026-05-20. Inclusion in KEV means CISA has confirmed in-the-wild exploitation.

How do I patch CVE-2009-1537?

Apply the security update from Microsoft for DirectX. Federal agencies must remediate by 2026-06-03 under BOD 22-01. Refer to the Microsoft Security Response Center for the official patch.

What type of vulnerability is CVE-2009-1537?

CVE-2009-1537 is classified under CWE-158.

What is the CVSS score for CVE-2009-1537?

CVE-2009-1537 has a CVSS 3.1 base score of 8.8, classifying it as High severity. The attack vector is Network, attack complexity is Low, and no privileges are required.