Description

Fireshare facilitates self-hosted media and link sharing. Prior to version 1.6.14, an argument Injection in the video upload function allows unauthenticated attacker to write/overwrite system files. Version 1.6.14 fixes the issue.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "9.8",
  "pubDate": "2026-09-15T21:16:36.920Z",
  "pubdate": "2026-09-15T21:16:36.920Z",
  "executiveSummary": "Fireshare versions prior to 1.6.14 contain a critical argument injection vulnerability within the video upload functionality.\nThis security flaw allows an unauthenticated, remote attacker to manipulate command-line arguments, leading to arbitrary file write or overwrite operations on the host system.\nThe vulnerability poses a severe risk to system integrity and confidentiality, as it grants unauthorized actors the ability to modify critical files or configuration data without requiring prior authentication.\nSuccessful exploitation depends on the attacker's ability to trigger the vulnerable video upload process while supplying crafted malicious input that influences system-level execution contexts.\nGiven the nature of argument injection, the potential impact includes full system compromise, persistent backdoor installation, or denial of service through the destruction of system resources.\nOrganizations utilizing Fireshare are strongly advised to update to version 1.6.14 or later to remediate the flaw and prevent potential exploitation.",
  "technicalDetails": "The vulnerability resides within the video processing pipeline of the Fireshare application, specifically where user-supplied input is passed to system-level utilities for media handling.\nThe root cause is identified as improper neutralization of special characters and insufficient validation of input parameters before they are concatenated into command-line strings executed by the underlying operating system.\nWhen a user initiates a video upload, the application processes the file using external tools, such as FFmpeg or similar media processors. An attacker can leverage the argument injection vulnerability by crafting a malicious payload within the metadata or the filename of the uploaded video.\nThe attack flow proceeds as follows: First, the attacker identifies the video upload endpoint. Second, the attacker submits a request containing a crafted filename or metadata field that includes shell-metacharacters or specific command-line flags (e.g., --output-file or redirect operators).\nBecause the application fails to properly sanitize these inputs, the injected characters are interpreted by the host operating system's command shell as intended operational arguments rather than simple data strings.\nThis allows the attacker to redirect the output of the video processing utility to an arbitrary location on the filesystem. By controlling the destination path, the attacker can overwrite sensitive configuration files, overwrite binary executables, or inject malicious scripts into system directories.\nThe exploitation does not require valid credentials, as the vulnerable endpoint is accessible to unauthenticated users, significantly increasing the risk of widespread, automated exploitation attempts.\nPost-exploitation impact is catastrophic, as the ability to write files allows for remote code execution (RCE) by overwriting application source code, configuration files that control server behavior, or system startup scripts.\nThe vulnerability exists in all Fireshare versions prior to 1.6.14. It is essential to ensure that input handling logic adheres to secure coding practices, such as using parameterized API calls instead of direct command-line string construction."
}