CVE-2001-1511 in JRun
Summary
by MITRE
JRun 3.0 and 3.1 running on JRun Web Server (JWS) and IIS allows remote attackers to read arbitrary JavaServer Pages (JSP) source code via a request URL containing the source filename ending in (1) "jsp%00" or (2) "js%2570".
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Analysis
by VulDB Data Team • 05/24/2019
This vulnerability exists in JRun 3.0 and 3.1 web server implementations that operate on both JRun Web Server and Internet Information Services platforms. The flaw represents a critical information disclosure vulnerability that allows remote attackers to access sensitive source code files through manipulated URL requests. The vulnerability stems from improper input validation and handling of special characters in file path resolution mechanisms, creating a pathway for unauthorized code retrieval.
The technical exploitation occurs through specific URL manipulation techniques that leverage null byte injection and URL encoding bypass methods. Attackers can append either "jsp%00" or "js%2570" to file requests to access JSP source code files. The %00 represents a null byte character that can terminate string processing in certain contexts, while %2570 is the URL encoded representation of "jsp" that bypasses standard validation filters. This dual approach demonstrates the vulnerability's susceptibility to multiple attack vectors and encoding manipulation techniques.
The operational impact of this vulnerability is severe as it exposes sensitive source code that may contain database connection strings, authentication credentials, business logic, and application architecture details. Such information disclosure provides attackers with comprehensive knowledge of the target system's internal workings, enabling more sophisticated attacks including privilege escalation, data manipulation, and further exploitation. The vulnerability affects the entire JRun application server ecosystem and can compromise multiple applications running on the same platform.
This vulnerability maps to CWE-174, which describes the weakness of "Single Character Substitution in an Identifier" and CWE-475, "Undefined Behavior for Input to API." The attack patterns align with TTPs found in the ATT&CK framework under the initial access and credential access phases, specifically targeting information gathering and reconnaissance activities. The vulnerability also demonstrates characteristics of path traversal and file inclusion attacks that are commonly classified under the attack techniques for privilege escalation and data theft.
Mitigation strategies should include immediate implementation of input validation controls that properly sanitize all file path requests and reject suspicious character sequences including null bytes and encoded special characters. System administrators must update to patched versions of JRun 3.0 and 3.1 or migrate to supported server versions that address these input validation flaws. Network-level protections such as web application firewalls should be configured to detect and block requests containing the specific attack patterns mentioned in the vulnerability. Additionally, implementing proper access controls and file permissions can limit the exposure of source code files even if the vulnerability is exploited. Regular security assessments and code reviews should be conducted to identify similar input validation weaknesses in other applications and systems.