CVE-2025-27481
CVE-2025-27481: Stack-based Buffer Overflow in Windows Telephony Service
Description: A stack-based buffer overflow vulnerability exists in the Windows Telephony Service (also known as TAPI or Telephony Application Programming Interface). This flaw allows a remote, unauthorized attacker to execute arbitrary code on a vulnerable system.
Severity:
- CVSS Score: 8.8 (High)
- Vector: AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H (Network, Low Attack Complexity, No Privileges Required, No User Interaction, Unchanged Scope, High Confidentiality Impact, High Integrity Impact, High Availability Impact)
Known Exploit: Publicly available exploit code allows remote, unauthenticated attackers to leverage the buffer overflow to achieve remote code execution.
Remediation/Mitigation Strategy:
Apply Security Update: Immediately apply the security update provided by Microsoft to address CVE-2025-27481. This is the primary and most effective remediation measure. Refer to Microsoft Security Advisory for specific patch details and download locations.
Disable Telephony Service (TAPI) (If Not Required): If the Windows Telephony Service is not essential for system functionality, consider disabling it. This will prevent exploitation of the vulnerability by removing the attack vector. To disable the service:
- Open the Services application (services.msc).
- Locate the “Telephony” service.
- Right-click and select “Properties.”
- Under the “General” tab, change the “Startup type” to “Disabled.”
- Click “Apply” and then “OK.”
- Restart the system.
Network Segmentation: Implement network segmentation to isolate vulnerable systems from untrusted networks. This limits the potential impact of a successful exploit by restricting attacker movement.
Monitor Network Traffic: Implement network intrusion detection and prevention systems (IDS/IPS) and closely monitor network traffic for suspicious activity related to exploitation attempts against the Telephony Service. Create alerts for unusual network activity targeting port 135 and other ports associated with the Telephony Service.
Principle of Least Privilege: Ensure that user accounts have only the minimum necessary privileges to perform their required tasks. This limits the potential damage an attacker can inflict if they gain access to a compromised account.
Enable Windows Firewall: Ensure the Windows Firewall is enabled and configured to block unnecessary incoming connections. This can help prevent unauthorized access to the Telephony Service.
Regular Security Audits and Vulnerability Scanning: Conduct regular security audits and vulnerability scanning to identify and remediate vulnerabilities promptly. Use a vulnerability scanner that is regularly updated with the latest vulnerability signatures.
Assigner
- Microsoft Corporation [email protected]
Date
- Published Date: 2025-04-08 17:23:59
- Updated Date: 2025-04-08 18:15:59