CVE-2012-1253 in Roundcube
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in Roundcube Webmail before 0.7, when Internet Explorer is used, allows remote attackers to inject arbitrary web script or HTML via vectors involving an embedded image attachment.
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Analysis
by VulDB Data Team • 12/03/2021
The vulnerability identified as CVE-2012-1253 represents a critical cross-site scripting flaw in Roundcube Webmail versions prior to 0.7, specifically affecting users utilizing Microsoft Internet Explorer browsers. This vulnerability stems from inadequate input validation and output encoding mechanisms within the webmail application's handling of embedded image attachments. The flaw manifests when the application processes image attachments without proper sanitization of user-supplied data, creating an avenue for malicious actors to execute arbitrary JavaScript code within the context of a victim's browser session.
The technical exploitation of this vulnerability occurs through the manipulation of image attachment metadata or filenames that contain malicious script code. When Internet Explorer processes these malformed attachments, the browser renders the embedded content without sufficient security controls, allowing the injected script to execute with the privileges of the logged-in user. This particular variant of XSS affects Internet Explorer specifically due to its different handling of certain HTML elements and script execution contexts compared to other browsers, making the vulnerability more prevalent in environments where IE is the primary browser. The vulnerability is categorized under CWE-79 as a failure to sanitize user input, specifically in the context of HTML output generation.
The operational impact of CVE-2012-1253 extends beyond simple script injection, potentially enabling attackers to perform session hijacking, data exfiltration, and privilege escalation within the webmail environment. An attacker could craft malicious email attachments that, when opened by a victim using Internet Explorer, would execute commands such as stealing authentication cookies, redirecting users to phishing sites, or even installing malware on the victim's system. The vulnerability's severity is amplified by the widespread use of Roundcube Webmail in enterprise environments and the prevalence of Internet Explorer in corporate settings, making successful exploitation particularly damaging. This vulnerability aligns with ATT&CK technique T1566.001 for initial access through spearphishing attachments and T1059.001 for command and control through script execution.
Mitigation strategies for this vulnerability involve immediate patching of Roundcube Webmail to version 0.7 or later, which implements proper input validation and output encoding for image attachment handling. Organizations should also implement content security policies that restrict script execution within email contexts and deploy web application firewalls to monitor and filter suspicious content. Browser security enhancements including the use of modern browsers with better XSS protection mechanisms and strict security settings can provide additional defense layers. Regular security assessments and input validation testing should be conducted to prevent similar vulnerabilities in other webmail applications. The vulnerability demonstrates the critical importance of proper input sanitization in web applications and the necessity of comprehensive security testing across different browser environments.