CVE-2017-8550 in Skype for Business
Summary
by MITRE
A remote code execution vulnerability exists in Skype for Business when the software fails to sanitize specially crafted content, aka "Skype for Business Remote Code Execution Vulnerability".
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Analysis
by VulDB Data Team • 09/13/2024
The CVE-2017-8550 vulnerability represents a critical remote code execution flaw in Skype for Business software that emerged from inadequate input validation mechanisms within the application's content handling processes. This vulnerability stems from the application's failure to properly sanitize user-supplied content, creating a pathway for malicious actors to execute arbitrary code on affected systems. The flaw specifically manifests when Skype for Business processes specially crafted content that contains malicious payloads, allowing attackers to bypass security controls and gain unauthorized access to the underlying system infrastructure.
From a technical perspective, this vulnerability operates through a classic input sanitization failure that aligns with CWE-20, which describes improper input validation in software systems. The flaw occurs during the processing of rich content formats that Skype for Business accepts, particularly affecting how the application handles embedded objects and multimedia elements within communication sessions. Attackers can exploit this weakness by crafting malicious content that, when processed by the vulnerable software, triggers unintended code execution sequences. The vulnerability's remote nature means that exploitation can occur without requiring physical access to the target system, making it particularly dangerous in enterprise environments where Skype for Business is widely deployed.
The operational impact of CVE-2017-8550 extends beyond simple remote code execution, as it provides attackers with a foothold for broader network infiltration and persistent access. Organizations using Skype for Business are at risk of complete system compromise when this vulnerability is exploited, potentially enabling attackers to establish backdoors, exfiltrate sensitive data, or deploy additional malware. The vulnerability's presence in communication software creates additional risks as attackers can leverage it to target not just individual endpoints but entire network infrastructures. This aligns with ATT&CK technique T1203, which covers legitimate credentials and software exploitation, as the vulnerability can be used to escalate privileges and maintain persistent access to enterprise networks.
Mitigation strategies for CVE-2017-8550 should include immediate deployment of Microsoft security updates that address the input sanitization flaws in Skype for Business. Organizations must also implement network segmentation to limit the potential impact of exploitation, particularly by isolating communication systems from critical infrastructure. Additional defensive measures include monitoring for unusual network traffic patterns that might indicate exploitation attempts, implementing strict content filtering policies for incoming communications, and conducting regular security assessments of collaboration software deployments. Security teams should also consider deploying endpoint detection and response solutions that can identify anomalous behavior indicative of exploitation attempts, as the vulnerability may be used as a stepping stone for more sophisticated attacks within compromised networks. The vulnerability's classification under CVE-2017-8550 underscores the importance of maintaining current security patches and implementing comprehensive software lifecycle management practices to prevent similar issues in other enterprise applications.