CVE-2011-3365 in KDE
Summary
by MITRE
The KDE SSL Wrapper (KSSL) API in KDE SC 4.6.0 through 4.7.1, and possibly earlier versions, does not use a certain font when rendering certificate fields in a security dialog, which allows remote attackers to spoof the common name (CN) of a certificate via rich text.
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Analysis
by VulDB Data Team • 01/09/2025
The vulnerability identified as CVE-2011-3365 resides within the KDE SSL Wrapper (KSSL) API implementation in KDE Software Compilation versions 4.6.0 through 4.7.1, with potential exposure in earlier releases. This security flaw represents a sophisticated user interface deception mechanism that exploits the rendering behavior of certificate fields within KDE's security dialogs. The issue specifically manifests when the KSSL API processes certificate information for display, creating an opportunity for malicious actors to manipulate visual representations of certificate data through carefully crafted rich text content.
The technical mechanism behind this vulnerability involves the improper handling of font rendering within the certificate display functionality of KDE's security interface. When certificate fields are rendered in the security dialog, the KSSL API fails to consistently apply a specific font that would normally ensure proper text rendering and verification. This inconsistency allows attackers to inject rich text elements that can alter how certificate information appears to users, particularly targeting the common name field which serves as a critical identifier for certificate authenticity. The vulnerability stems from the API's failure to properly sanitize or validate the font usage when displaying certificate details, creating a window for visual spoofing attacks.
The operational impact of this vulnerability extends beyond simple visual deception to potentially compromise the security posture of systems relying on KDE's SSL certificate validation mechanisms. Attackers can exploit this weakness to create convincing fake certificate dialogs that appear legitimate to users, potentially leading to successful phishing attacks or man-in-the-middle scenarios where users might unknowingly trust malicious certificates. This type of attack directly undermines the trust model that SSL/TLS certificates are designed to establish, as users may be misled into believing they are connecting to a legitimate secure service when they are actually interacting with an attacker-controlled endpoint. The vulnerability particularly affects users who rely on KDE-based desktop environments for web browsing and secure communications, making it a significant concern for organizations utilizing KDE software stacks.
The security implications of CVE-2011-3365 align with CWE-601 vulnerability class, which encompasses URL redirector abuse and user interface deception mechanisms. This classification reflects the core issue of misleading users through manipulated visual representations within the security interface. From an ATT&CK framework perspective, this vulnerability maps to techniques involving social engineering through user interface manipulation and credential access through deception. The attack surface is particularly relevant in environments where users interact with web applications through KDE browsers or applications that leverage the KSSL API for certificate validation. Organizations should consider this vulnerability as part of their broader security awareness training, as it demonstrates how seemingly benign UI rendering issues can create significant security risks. The recommended mitigation strategy involves upgrading to patched versions of KDE Software Compilation, specifically versions beyond 4.7.1, along with implementing additional monitoring for suspicious certificate validation behaviors. System administrators should also consider deploying certificate pinning mechanisms and enhanced user education regarding certificate verification practices to reduce the risk of successful exploitation.
This vulnerability demonstrates the critical importance of proper input validation and consistent rendering behavior in security-critical user interface components. The flaw illustrates how subtle implementation details in cryptographic user interfaces can create exploitable conditions that bypass traditional security controls. Organizations should recognize that user interface security is not merely about aesthetics but represents a fundamental aspect of trust establishment in secure communications. The incident underscores the necessity of thorough security testing of GUI components that handle sensitive information, particularly those involved in certificate validation and trust establishment processes.