Horizon Alert
Summary of the vulnerability and why it matters
A critical vulnerability in Skype for Business could allow unauthorized attackers to execute code over a network by manipulating file names. This issue is particularly concerning due to the potential for remote code execution, which attackers could leverage to compromise systems. The primary concern for leadership is to confirm if this technology is in use and assess potential exposure.
- Attackers can run unauthorized code remotely.
- Critical flaw impacts business communication systems.
- Confirm relevance and potential exposure immediately.
Attack Path
How an attacker could exploit the issue
An attacker could exploit this vulnerability by sending a specially crafted network request to a vulnerable Skype for Business instance. This request targets a weakness in how the application handles file names or paths, allowing the attacker to potentially execute arbitrary code on the server. Successful exploitation could lead to a complete compromise of the affected system, enabling an attacker to perform unauthorized actions over a network.
- No authentication or privileges needed.
- Network request with malicious file path.
- Remote code execution and system compromise.
Live Threat
Current exploitation, exposure, and threat context
An attacker could execute code over a network by manipulating file names or paths in Skype for Business, when supported by the advisory's described conditions. This could allow for unauthorized code execution, impacting the confidentiality, integrity, and availability of the affected system.
- Code execution on the system.
- Exploiting file path vulnerabilities.
- Compromised system confidentiality and integrity.
Operational Fix
Recommended remediation, mitigation, and detection steps
This vulnerability in Skype for Business, allowing network code execution via external control of file paths, likely falls under the responsibility of the platform or infrastructure teams managing the application, in coordination with the vendor management team for patching or updates. The immediate first step is to identify all Skype for Business deployments, confirm their network exposure and business criticality, and then assign an accountable owner to prioritize and plan remediation based on assessed risk.
- Platform and infrastructure teams own resolution.
- Verify network exposure and business criticality.
- Plan coordinated updates and mitigation.
