CVE-2015-4220 in Unified Presence Server
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in Cisco Unified Presence Server 9.1(1) allows remote attackers to inject arbitrary web script or HTML via an unspecified value, aka Bug ID CSCuq03773.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 05/21/2022
The vulnerability identified as CVE-2015-4220 represents a cross-site scripting flaw within Cisco Unified Presence Server version 9.1(1) that exposes systems to remote code execution through malicious web script injection. This vulnerability specifically affects the server's handling of unspecified input values, creating a pathway for attackers to execute arbitrary code within the context of a victim's browser session. The issue stems from insufficient input validation and output encoding mechanisms that fail to properly sanitize user-supplied data before processing or rendering within web interfaces. Cisco's Unified Presence Server serves as a critical communication platform that integrates presence information with unified messaging systems, making this vulnerability particularly dangerous as it could compromise the integrity of enterprise communication networks. The vulnerability is catalogued under CWE-79 which specifically addresses Cross-Site Scripting flaws, emphasizing the fundamental weakness in input sanitization and output encoding practices. From an operational standpoint, this vulnerability aligns with ATT&CK technique T1566.001 which focuses on spearphishing attachments, as attackers could leverage this XSS flaw to deliver malicious payloads through crafted web content that appears legitimate to end users. The impact extends beyond simple script injection as it could enable attackers to hijack user sessions, steal sensitive presence information, or redirect users to malicious sites that could further compromise the network. Attackers exploiting this vulnerability could potentially access real-time presence data, user credentials, or other sensitive information that the Unified Presence Server manages. The vulnerability's remote exploitability means that attackers do not require physical access or local network privileges to launch attacks, making it particularly dangerous in enterprise environments where the server typically operates in accessible network segments. Organizations utilizing Cisco Unified Presence Server 9.1(1) face significant risk of unauthorized access and data compromise, as the flaw allows attackers to execute malicious code in the context of authenticated users. The vulnerability demonstrates a critical gap in the server's security architecture where user input is not adequately filtered or escaped before being rendered in web interfaces. Security researchers have identified this as a high-severity issue due to its remote exploitability and potential for privilege escalation, as presence information often includes sensitive user data and system access details. The flaw essentially creates a persistent backdoor for attackers to maintain access to the communication infrastructure while potentially gaining insights into user behavior patterns and system configurations. Organizations should implement immediate mitigations including applying Cisco's security patches, implementing web application firewalls, and conducting thorough security assessments of their presence server configurations. The vulnerability also highlights the importance of input validation and output encoding practices as recommended in OWASP Top Ten security guidelines, particularly focusing on preventing XSS attacks through proper data sanitization and context-appropriate output encoding. Network segmentation and access controls should be strengthened to limit exposure of the Unified Presence Server to untrusted networks, while regular monitoring of web application logs can help detect potential exploitation attempts. Additionally, security awareness training for administrators and users should emphasize the risks associated with clicking on suspicious links or visiting untrusted websites that could leverage such vulnerabilities to compromise enterprise communication systems.