Description

Unauthenticated Local File Inclusion in Shuffle <= 1.8 versions.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "8.1",
  "pubDate": "2026-08-20T12:16:30.777Z",
  "pubdate": "2026-08-20T12:16:30.777Z",
  "executiveSummary": "An unauthenticated Local File Inclusion (LFI) vulnerability affects Shuffle <= 1.8 versions. This security flaw allows remote, unauthenticated attackers to traverse the file system and access arbitrary sensitive files residing on the host operating system. The vulnerability poses a severe risk to confidentiality, potentially exposing critical system files, application source code, and configuration data containing sensitive credentials. Exploitation requires network access to the vulnerable Shuffle instance but does not necessitate prior authentication or specialized privileges. The root cause stems from insufficient input sanitization and validation within the affected file retrieval or rendering mechanisms, failing to adequately restrict path traversal sequences such as dot-dot-slash patterns. Consequently, threat actors can craft malicious HTTP requests incorporating directory traversal payloads to retrieve unauthorized system resources directly. Immediate remediation requires updating Shuffle beyond version 1.8 or applying vendor-supplied patches to restrict file access boundaries and enforce strict input validation protocols across all affected components.",
  "technicalDetails": "The vulnerability is classified as a Local File Inclusion (LFI) affecting Shuffle <= 1.8 versions, characterized by a lack of proper input sanitization and path validation in file handling routines. Specifically, the vulnerable component fails to adequately filter directory traversal sequences (such as relative path notation like ../) supplied via user-controlled input parameters within HTTP requests. The attack surface is exposed over the network, allowing any unauthenticated remote actor to interact directly with the web application without requiring valid session tokens, credentials, or elevated privileges. The exploitation method involves constructing a specially crafted URI or HTTP request containing path traversal payloads designed to break out of the intended web root directory and navigate the underlying host file system. Upon receiving the malicious payload, the application processes the parameter insecurely, passing the relative file path directly to internal file reading functions or system APIs. The vulnerable function reads the targeted file from the disk—such as /etc/passwd or application configuration files—and includes its contents directly into the HTTP response returned to the client. The attack flow proceeds as follows: first, the unauthenticated attacker probes the Shuffle instance to identify endpoints handling file parameters; second, the attacker injects traversal sequences coupled with target file paths; third, the backend application evaluates the unsanitized path and opens the requested resource; and fourth, the sensitive file contents are exfiltrated via the application response. The post-exploitation impact includes the potential exposure of sensitive system files, database credentials, API keys, and internal configuration details, which can facilitate further lateral movement, privilege escalation, or full system compromise depending on the permissions of the user account executing the Shuffle service."
}