CVE-2015-1877 in Xdg-utils
Summary
by MITRE • 06/02/2021
The open_generic_xdg_mime function in xdg-open in xdg-utils 1.1.0 rc1 in Debian, when using dash, does not properly handle local variables, which allows remote attackers to execute arbitrary commands via a crafted file.
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Analysis
by VulDB Data Team • 11/29/2024
The vulnerability identified as CVE-2015-1877 resides within the xdg-open utility component of xdg-utils version 1.1.0 rc1, specifically affecting Debian distributions. This flaw manifests in the open_generic_xdg_mime function where improper handling of local variables creates a command injection opportunity. The vulnerability is particularly concerning because xdg-open serves as a core utility for opening files and URLs according to user preferences, making it a critical component in desktop environments that could be exploited by malicious actors.
The technical implementation of this vulnerability stems from the function's inadequate sanitization of input parameters when processing MIME type associations. When dash shell is used as the command interpreter, the improper variable handling allows attackers to inject malicious commands through crafted file names or content that get processed by the vulnerable function. This represents a classic command injection flaw that aligns with CWE-78, which specifically addresses improper neutralization of special elements used in OS commands. The vulnerability is particularly dangerous in desktop environments where users might encounter malicious files or URLs that trigger the vulnerable code path.
The operational impact of this vulnerability extends beyond simple command execution, as it can enable attackers to escalate privileges and compromise the entire desktop environment. Remote attackers can craft malicious files or web content that, when opened through the vulnerable xdg-open utility, executes arbitrary code with the privileges of the user running the application. This attack vector is particularly dangerous in multi-user environments or when users have elevated privileges, as it could allow for complete system compromise. The ATT&CK framework categorizes this as a command injection technique under the T1059.001 sub-technique, which represents the execution of commands through the command and scripting interpreter.
Mitigation strategies for CVE-2015-1877 require immediate patching of the xdg-utils package to the latest stable version that addresses the variable handling issue. System administrators should also implement proper input validation and sanitization measures for file names and content that might be processed through the xdg-open utility. Network segmentation and user access controls can help limit the potential impact of exploitation by restricting access to potentially malicious content. Additionally, monitoring for suspicious command execution patterns and implementing application whitelisting policies can provide defense-in-depth measures against exploitation attempts. The vulnerability demonstrates the critical importance of proper input validation in system utilities and highlights how seemingly benign desktop components can become attack vectors when not properly secured against command injection attacks.