CVE-2018-25059 in pastebinit
Summary
by MITRE • 12/30/2022
A vulnerability was found in pastebinit up to 0.2.2 and classified as problematic. Affected by this issue is the function pasteHandler of the file server.go. The manipulation of the argument r.URL.Path leads to path traversal. Upgrading to version 0.2.3 is able to address this issue. The name of the patch is 1af2facb6d95976c532b7f8f82747d454a092272. It is recommended to upgrade the affected component. The identifier of this vulnerability is VDB-217040.
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Analysis
by VulDB Data Team • 01/26/2023
The vulnerability identified as CVE-2018-25059 affects pastebinit version 0.2.2 and earlier, representing a critical path traversal flaw within the server.go file. This vulnerability specifically targets the pasteHandler function where the application fails to properly sanitize the r.URL.Path argument, creating an exploitable condition that allows attackers to manipulate file paths and potentially access unauthorized system resources. The flaw resides in the application's handling of URL path components without adequate validation or sanitization mechanisms, making it susceptible to directory traversal attacks. The vulnerability is classified under CWE-22 which specifically addresses path traversal or directory traversal issues, where improper input validation allows attackers to access files or directories outside the intended scope. This weakness enables adversaries to navigate the file system beyond the designated boundaries, potentially accessing sensitive configuration files, system binaries, or other restricted resources.
The operational impact of this vulnerability extends beyond simple information disclosure, as it provides attackers with the capability to execute arbitrary file system operations. When an attacker manipulates the r.URL.Path parameter, they can craft malicious requests that traverse directories using sequences like "../" to move up the file system hierarchy. This allows for unauthorized access to system files, configuration data, or potentially even system commands if the application has insufficient access controls or proper input validation. The vulnerability affects the core functionality of pastebinit's server component, which is designed to handle paste operations through HTTP requests, making it particularly dangerous in environments where the service is exposed to untrusted networks or users. The attack surface is widened when the service operates with elevated privileges or has access to sensitive system resources, as the path traversal could potentially lead to privilege escalation or system compromise.
Mitigation strategies for CVE-2018-25059 primarily focus on upgrading to version 0.2.3 or later, which incorporates the patch identified by the commit hash 1af2facb6d95976c532b7f8f82747d454a092272. This upgrade addresses the root cause by implementing proper input sanitization and validation for URL path components within the pasteHandler function. Organizations should also implement additional defensive measures including restricting access to the pastebinit service, implementing proper authentication mechanisms, and monitoring for suspicious path traversal attempts. The remediation aligns with ATT&CK technique T1059.007 which covers command and scripting interpreter usage, as attackers may leverage path traversal to access system binaries or scripts. Network segmentation and firewall rules should be configured to limit access to the pastebinit service to trusted networks only, while also implementing web application firewalls that can detect and block suspicious path traversal patterns. Regular security audits and input validation reviews should be conducted to ensure similar vulnerabilities are not present in other components of the system.
The vulnerability demonstrates the critical importance of proper input validation in web applications, particularly those handling user-supplied URL parameters. The flaw represents a classic example of how insufficient sanitization of user input can lead to severe security consequences, aligning with industry best practices outlined in OWASP Top Ten and NIST guidelines for secure coding. Organizations should consider implementing automated security scanning tools that can detect similar path traversal vulnerabilities in their codebases, as well as establishing secure coding practices that emphasize input validation and proper resource access controls. The patch for this vulnerability specifically addresses the function's handling of URL paths by implementing proper path validation and normalization, preventing the exploitation of directory traversal sequences that could otherwise be used to access unauthorized resources.