CVE-2002-0771 in ViewCVS
Summary
by MITRE
Cross-site scripting vulnerability in viewcvs.cgi for ViewCVS 0.9.2 allows remote attackers to inject script and steal cookies via the (1) cvsroot or (2) sortby parameters.
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Analysis
by VulDB Data Team • 09/14/2025
The vulnerability identified as CVE-2002-0771 represents a critical cross-site scripting flaw in ViewCVS 0.9.2's viewcvs.cgi script, which falls under the CWE-79 category of Cross-Site Scripting. This vulnerability specifically affects the web interface of ViewCVS, a web-based interface for viewing cvs repository contents, making it susceptible to malicious script injection attacks that can compromise user sessions and data integrity. The flaw exists in how the application processes user input parameters without adequate sanitization or output encoding, creating an avenue for attackers to execute arbitrary scripts in the context of authenticated users.
The technical implementation of this vulnerability occurs through two primary attack vectors involving the cvsroot and sortby parameters within the viewcvs.cgi script. When these parameters are passed directly to the web interface without proper input validation or sanitization, attackers can inject malicious javascript code that executes in the victim's browser. The vulnerability is particularly concerning because it allows attackers to steal session cookies, which can then be used to impersonate legitimate users and gain unauthorized access to the CVS repositories. This type of attack aligns with ATT&CK technique T1539 which describes credentials in files, and T1059 which covers command and scripting interpreter, as the malicious scripts can execute within the user's browser context.
The operational impact of CVE-2002-0771 extends beyond simple script injection, as successful exploitation can lead to complete session hijacking and unauthorized repository access. Attackers leveraging this vulnerability can steal authentication cookies, potentially gaining access to sensitive source code repositories and compromising the integrity of the development environment. The attack requires minimal sophistication and can be executed through simple URL manipulation, making it particularly dangerous in environments where developers and administrators frequently access CVS repositories through web interfaces. The vulnerability affects all users of ViewCVS 0.9.2 who interact with the viewcvs.cgi script, particularly those who may be accessing repositories containing sensitive or proprietary source code.
Mitigation strategies for this vulnerability should prioritize immediate patching of the affected ViewCVS version to the latest stable release, which includes proper input sanitization and output encoding mechanisms. Organizations should implement proper parameter validation and sanitization for all user-supplied input, particularly in web applications that process repository access parameters. The implementation of Content Security Policy headers can provide additional protection against script injection attempts, while proper output encoding of parameters before display in web interfaces prevents malicious scripts from executing. Security teams should also consider implementing web application firewalls to detect and block suspicious parameter patterns, and conduct regular security assessments to identify similar vulnerabilities in other web applications within the organization's infrastructure. The remediation process should include comprehensive testing to ensure that all input parameters are properly sanitized and that the application maintains secure output handling practices to prevent similar cross-site scripting vulnerabilities from emerging in the future.