CVE-2016-6217 in PureMessage for UNIX
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in Sophos PureMessage for UNIX before 6.3.2 allows remote attackers to inject arbitrary web script or HTML via unspecified vectors.
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Analysis
by VulDB Data Team • 12/28/2019
The CVE-2016-6217 vulnerability represents a critical cross-site scripting flaw in Sophos PureMessage for UNIX versions prior to 6.3.2, exposing organizations to significant web application security risks. This vulnerability falls under the CWE-79 category of Cross-Site Scripting, which is classified as a common weakness in web application security frameworks. The flaw enables remote attackers to inject malicious scripts or HTML content into the target system through unspecified attack vectors, potentially compromising user sessions and data integrity. Sophos PureMessage for UNIX serves as an email security solution that filters and processes email traffic, making it a critical component in enterprise email infrastructure. The vulnerability's presence in this security tool creates a dangerous paradox where an application designed to protect against malicious email content becomes a potential entry point for attackers to exploit.
The technical implementation of this XSS vulnerability demonstrates how improperly sanitized input handling can lead to severe security consequences in email processing systems. Attackers can leverage this flaw by crafting malicious email messages or web interface inputs that contain embedded scripts, which are then executed in the context of other users' browsers when they interact with the affected system. The unspecified vectors suggest that the vulnerability may manifest through multiple entry points within the email processing pipeline, potentially including message headers, body content, or administrative web interfaces. This broad attack surface increases the exploitability factor and makes comprehensive protection more challenging for security administrators. The vulnerability's classification as a remote attack vector means that adversaries do not require local access or physical presence to exploit the flaw, making it particularly dangerous in networked environments.
The operational impact of CVE-2016-6217 extends beyond simple script injection, potentially enabling more sophisticated attacks such as session hijacking, credential theft, and data exfiltration. Organizations relying on Sophos PureMessage for UNIX may experience unauthorized access to email content, compromise of user accounts, and potential lateral movement within their network infrastructure. The vulnerability's presence in an email security solution creates a particularly concerning scenario where attackers can bypass the very security controls designed to protect against malicious email content. This weakness directly violates the principle of least privilege and can lead to unauthorized access to sensitive organizational communications. The attack could result in significant business disruption, regulatory compliance violations, and potential financial losses due to data breaches or service interruptions.
Mitigation strategies for CVE-2016-6217 should prioritize immediate patch deployment to Sophos PureMessage for UNIX versions before 6.3.2, as this represents the most effective solution to address the vulnerability. Organizations should also implement additional defensive measures including enhanced input validation, web application firewalls, and regular security assessments of their email infrastructure. The implementation of Content Security Policy headers and proper output encoding can provide additional protection layers against XSS attacks, aligning with ATT&CK framework techniques for defensive measures. Security teams should conduct comprehensive vulnerability assessments to identify other potential XSS vulnerabilities in related systems and ensure proper security hardening of the email processing environment. Regular monitoring and incident response procedures should be established to detect and respond to potential exploitation attempts, while also implementing network segmentation to limit the potential impact of successful attacks.