CVE-2012-0956 in ubiquity-slideshow-ubuntu
Summary
by MITRE
ubiquity-slideshow-ubuntu before 58.2, during installation, allows remote man-in-the-middle attackers to execute arbitrary web script or HTML and read arbitrary files via a crafted attribute in the <a> tag of a Twitter feed.
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Analysis
by VulDB Data Team • 01/02/2025
The vulnerability identified as CVE-2012-0956 represents a critical security flaw in the ubiquity-slideshow-ubuntu package version 58.2 and earlier, which operates during the Ubuntu installation process. This vulnerability stems from inadequate input validation and sanitization mechanisms within the slideshow component that processes Twitter feed data. The flaw specifically manifests when the system parses HTML content from Twitter feeds, particularly targeting the anchor tag <a> element where malicious attributes can be injected to execute arbitrary code.
The technical implementation of this vulnerability exploits a classic cross-site scripting attack vector combined with file inclusion mechanisms. Attackers can craft malicious Twitter feed content containing specially formatted attributes within the <a> tag that, when processed by the ubiquity-slideshow-ubuntu component, execute unintended web scripts or HTML code on the target system. This allows remote attackers to bypass normal security boundaries and gain unauthorized access to execute arbitrary commands. The vulnerability is particularly dangerous because it occurs during the installation phase when system security controls may be less stringent and user interaction is expected.
The operational impact of this vulnerability extends beyond simple code execution, as it provides attackers with the ability to read arbitrary files from the system. This dual capability of code execution and file reading creates a comprehensive attack surface that could lead to complete system compromise. During Ubuntu installation, attackers could potentially access sensitive configuration files, user credentials, or system binaries that would otherwise remain protected. The timing of the vulnerability during installation makes it particularly attractive to attackers as the target systems are in a vulnerable state with elevated privileges and minimal security restrictions.
This vulnerability aligns with CWE-79 Cross-site Scripting and CWE-22 Improper Limitation of a Pathname to a Restricted Directory, demonstrating how improper input validation can create multiple attack vectors. From an ATT&CK framework perspective, this vulnerability maps to T1059 Command and Scripting Interpreter and T1074 Data Staged, as attackers can execute commands and access staged data through the compromised installation process. The attack requires minimal privileges to initiate and can be executed remotely without authentication, making it particularly dangerous in automated or networked environments where installation processes may be triggered automatically.
Mitigation strategies should focus on implementing robust input sanitization and validation mechanisms during the installation process. System administrators should immediately upgrade to ubiquity-slideshow-ubuntu version 58.2 or later, which contains patches addressing the input validation flaws. Network-level protections including firewall rules and content filtering should be implemented to restrict access to Twitter feeds during installation phases. Additionally, organizations should consider implementing secure coding practices that validate all external input, particularly HTML content, and employ proper encoding techniques to prevent malicious attribute injection. Regular security assessments should verify that no other components within the installation process are vulnerable to similar input manipulation attacks.