CVE-2012-0878 in Paste
Summary
by MITRE
Paste Script 1.7.5 and earlier does not properly set group memberships during execution with root privileges, which might allow remote attackers to bypass intended file-access restrictions by leveraging a web application that uses the local filesystem.
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Analysis
by VulDB Data Team • 01/02/2025
The vulnerability identified as CVE-2012-0878 affects Paste Script versions 1.7.5 and earlier, presenting a critical security flaw in how the system handles privilege escalation and group membership management. This issue manifests when Paste Script executes with root privileges, creating a scenario where the application fails to properly establish the correct group memberships during execution. The flaw represents a classic privilege escalation vulnerability that can be exploited by remote attackers to gain unauthorized access to restricted file systems. The vulnerability specifically impacts web applications that utilize Paste Script's local filesystem capabilities, making it particularly dangerous in environments where web applications interact with sensitive data repositories.
The technical root cause of this vulnerability lies in the improper handling of Unix group permissions during privilege elevation processes. When Paste Script executes with elevated privileges, it should maintain the correct group context to ensure proper access control enforcement. However, the implementation fails to correctly set group memberships, allowing the application to operate with reduced group privileges or incorrect group contexts. This misconfiguration creates a security boundary that can be exploited by attackers who craft malicious requests to web applications using Paste Script. The vulnerability is categorized under CWE-276, which deals with incorrect permissions for critical resources, and aligns with ATT&CK technique T1068, which addresses privilege escalation through improper privilege management. The flaw essentially allows attackers to bypass intended file-access restrictions that should normally prevent unauthorized data access.
The operational impact of this vulnerability extends beyond simple file access violations, as it can enable attackers to escalate their privileges and gain access to sensitive system resources that should remain protected. Web applications leveraging Paste Script can become entry points for attackers seeking to compromise the underlying system, particularly in environments where the application has write access to critical directories or where sensitive configuration files are stored. Attackers can exploit this weakness to read restricted files, modify system configurations, or potentially execute arbitrary code with elevated privileges. The vulnerability is particularly concerning because it operates at the privilege boundary level, meaning that even if an attacker cannot directly exploit the web application, they can leverage the misconfigured group memberships to bypass security controls. This type of vulnerability can lead to data breaches, system compromise, and potential lateral movement within network environments where Paste Script is deployed.
Mitigation strategies for CVE-2012-0878 should focus on immediate patching of affected Paste Script versions, with organizations upgrading to versions 1.7.6 or later where the group membership handling has been corrected. Additionally, system administrators should implement proper privilege separation by running web applications with minimal required privileges rather than root access, reducing the attack surface when such vulnerabilities are present. Network segmentation and access controls should be enforced to limit the exposure of applications using Paste Script to only necessary network segments. Security monitoring should include detection of unusual file access patterns and privilege escalation attempts that might indicate exploitation of this vulnerability. Organizations should also conduct comprehensive vulnerability assessments to identify all instances of Paste Script in their environments and ensure that proper security controls are in place to prevent exploitation of similar privilege escalation vulnerabilities. The remediation process should include implementing proper input validation and access control mechanisms within web applications that utilize Paste Script to further reduce the risk of exploitation.