CVE-2026-105157 in DocSys
Summary
by MITRE • 10/04/2026
A security vulnerability has been detected in RainyGao DocSys up to 2.02.85. The affected element is the function DocController.doGetTmp of the file /Doc/doGetTmpFile.do of the component Document Controller. The manipulation of the argument path/fileName leads to path traversal. Remote exploitation of the attack is possible. The exploit has been disclosed publicly and may be used. The project was informed of the problem early through an issue report but has not responded yet.
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Analysis
by VulDB Data Team • 10/04/2026
The vulnerability identified in RainyGao DocSys versions up to 2.02.85 represents a critical security flaw within the Document Controller component, specifically located in the function DocController.doGetTmp found in the file /Doc/doGetTmpFile.do. This issue is classified as a path traversal vulnerability, which falls under the Common Weakness Enumeration category CWE-22: Improper Limitation of a Pathname to a Restricted Directory. The core technical flaw stems from insufficient validation and sanitization of user-supplied input arguments, particularly those related to file paths or filenames passed via HTTP GET requests. When an attacker manipulates these parameters by injecting directory traversal sequences such as ../, the application fails to properly restrict access to only authorized directories. Instead, it interprets these sequences literally, allowing the underlying system to resolve file paths outside of the intended web root or secure storage area. This lack of input validation enables the remote server to retrieve arbitrary files from the filesystem based on the attacker's constructed path string.
The operational impact of this vulnerability is severe due to its potential for remote exploitation without authentication in many configurations, although specific access controls may vary depending on deployment settings. An unauthenticated or authenticated remote attacker can leverage this flaw to read sensitive system files that are not intended for public exposure. This includes configuration files containing database credentials, application secrets, private keys, and other internal logic details. In worst-case scenarios where the web server process runs with elevated privileges, reading critical operating system files could provide further insights into the host environment, potentially aiding in more sophisticated attacks such as privilege escalation or lateral movement within a network. The disclosure of public exploits significantly lowers the barrier to entry for malicious actors, increasing the likelihood of automated scanning and exploitation attempts against vulnerable instances deployed on the internet.
From an offensive security perspective, this vulnerability aligns with techniques described in the MITRE ATT&CK framework, specifically under Tactic: Collection (T1005) which involves data from local system sources, and potentially T1083: File and Directory Discovery if used to map out the server structure. The ability to traverse directories allows attackers to enumerate sensitive information stored on the backend file system, compromising confidentiality integrity of the application's data assets. Since the project maintainers have been notified via issue reports but have not yet responded or released a patch, organizations running this version are exposed to ongoing risk until mitigation is implemented locally or an upgrade becomes available.
To mitigate this vulnerability immediately, administrators should implement strict input validation on all file path parameters within the application code. This involves ensuring that any user-supplied filename or path component does not contain directory traversal characters such as dots and slashes in combinations that could escape the designated upload or document storage directories. Additionally, implementing a whitelist approach for allowed file extensions and using canonicalization techniques to resolve paths before processing can prevent exploitation attempts. If immediate code modification is not feasible, web application firewalls (WAFs) should be configured with rulesets capable of detecting and blocking HTTP requests containing path traversal patterns targeting the /Doc/doGetTmpFile.do endpoint. Furthermore, restricting file system permissions for the user account running the RainyGao DocSys service to limit read access only to necessary directories can reduce the impact if exploitation occurs. Until a patched version is released by the vendor, continuous monitoring of application logs for suspicious path manipulation attempts and regular security assessments are recommended to maintain defense in depth.