CVE-2026-77914 in rConfig
Summary
by MITRE • 08/24/2026
rConfig before 8.2.13 contains a path traversal vulnerability that allows authenticated users to read arbitrary files by supplying crafted filenames containing directory traversal sequences to the export download endpoint. Attackers can manipulate the filename parameter with traversal sequences to escape the intended export directory and access files outside it that are readable by the application process.
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Analysis
by VulDB Data Team • 08/24/2026
The rConfig software, a popular network configuration management tool used for automating backups of network devices such as routers and switches, suffered from a critical path traversal vulnerability in versions prior to 8.2.13. This flaw resides within the export download endpoint, which is designed to allow authenticated users to retrieve previously generated backup files or exported configurations. The underlying technical defect stems from insufficient validation and sanitization of user-supplied input specifically related to filename parameters. When a user requests an export file, the application constructs a local filesystem path by appending the provided filename to a base directory intended for exports. However, because the software fails to properly neutralize special characters that represent parent directories, such as dot-dot-slash sequences, it allows these traversal strings to manipulate the resulting path resolution logic.
From a technical perspective, this vulnerability is classified under CWE-22: Improper Limitation of a Pathname to a Restricted Directory. The core issue involves the application's failure to canonicalize or strictly validate the input before using it in file system operations. By injecting directory traversal sequences into the filename parameter, an attacker can alter the relative path structure. This manipulation enables the request to escape the confines of the designated export directory and traverse up through parent directories on the server's operating system. Consequently, the application may read files located outside the intended scope, provided that those external files are readable by the user account under which the rConfig web service or backend process is executing.
The operational impact of this vulnerability is significant for organizations relying on rConfig to manage sensitive network infrastructure data. An authenticated attacker can exploit this flaw to perform unauthorized file reads across the server's filesystem. This capability facilitates a broad range of malicious activities, including the exfiltration of configuration files that may contain hardcoded credentials, API keys, or other secrets stored in application configuration files such as .env or database connection strings. Furthermore, access to system-level files could reveal sensitive information about the operating environment, user accounts, and installed software versions, thereby aiding further reconnaissance and potential privilege escalation attacks. The severity is compounded by the fact that authentication is required, which may lead administrators to underestimate the risk compared to unauthenticated vulnerabilities, yet many enterprise deployments enforce strong authentication policies that do not mitigate this specific logic flaw.
In terms of threat modeling and industry standards, this vulnerability aligns with MITRE ATT&CK technique T1083: File and Directory Discovery. Attackers utilize path traversal as a primary method for enumerating the file system structure to locate valuable targets without triggering typical intrusion detection signatures associated with direct execution attempts. The exploitation chain typically involves logging in with valid credentials, navigating to the export or backup section of the interface, and submitting a crafted request where the filename parameter contains sequences like ../../etc/passwd or similar paths depending on the target operating system. This allows for silent data extraction without leaving obvious traces of brute-force activity or injection attempts that might be flagged by standard web application firewalls if not specifically tuned to detect traversal patterns in file download endpoints.
To mitigate this vulnerability, organizations running rConfig versions earlier than 8.2.13 must upgrade immediately to version 8.2.13 or later, where the developers have implemented proper input validation and path canonicalization checks. For environments where immediate patching is not feasible due to operational constraints, several defensive measures can be employed as compensating controls. Implementing a strict allowlist for permitted characters in filename inputs can prevent traversal sequences from being processed by the application logic. Additionally, deploying web application firewalls with rules specifically designed to detect and block directory traversal patterns in URL parameters or POST bodies can provide an external layer of defense. It is also advisable to ensure that the rConfig process runs under a restricted user account with minimal file system permissions, limiting the scope of files accessible even if path traversal occurs. Regular security audits and penetration testing focused on input validation flaws are recommended to identify similar weaknesses in other endpoints within the application.