Description

Unauthenticated Arbitrary File Upload in Tailored Tools <= 3.0.3 versions.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "9.0",
  "pubDate": "2026-10-10T20:16:38.870Z",
  "pubdate": "2026-10-10T20:16:38.870Z",
  "executiveSummary": "Tailored Tools versions 3.0.3 and below are susceptible to an unauthenticated arbitrary file upload vulnerability. This security flaw resides in the application's file handling mechanisms, allowing remote, unauthenticated attackers to bypass security controls and upload malicious files directly to the server. The vulnerability permits the arbitrary execution of code, which could result in a complete system compromise, unauthorized data exfiltration, or the establishment of persistent backdoors. Because the vulnerability does not require authentication or elevated privileges, the risk level is critical, as it allows threat actors to leverage the server as an initial access vector for broader network penetration. No specific user interaction is required for successful exploitation, making this a high-probability attack vector for exposed instances.",
  "technicalDetails": "The vulnerability manifests as an improper validation of file uploads, originating from a lack of server-side sanitization and type-checking mechanisms within the input handling logic of Tailored Tools <= 3.0.3. The root cause is the application's failure to enforce strict allow-lists for file extensions, MIME types, or content headers, allowing an attacker to submit arbitrary binary payloads through standard HTTP POST requests.\nThe exploitation flow begins with an attacker identifying the endpoint responsible for file processing. By bypassing the client-side validation—often implemented merely through JavaScript filters—an attacker can transmit a multipart/form-data request containing a malicious payload (e.g., a web shell or executable script). Because the system does not sufficiently validate the file path or destination directory, the application stores the uploaded file within the web-accessible root or an execution-permitted directory.\nOnce the file is uploaded, the attacker can execute the payload by making a direct HTTP request to the file's URI. The server-side environment then parses the malicious code, granting the attacker the effective privileges of the web service process. This provides the capability to execute system-level commands, modify the application state, read sensitive configuration files, or interact with backend databases.\nThis vulnerability is particularly severe due to the absence of authentication requirements; it exposes the web server to the public internet without requiring the attacker to possess valid credentials or establish a session. The impact of successful exploitation includes remote code execution (RCE), which facilitates lateral movement within the hosting infrastructure. Post-exploitation activities typically involve the deployment of long-term persistence mechanisms, such as modified web shells that reside on the filesystem, effectively turning the server into a command-and-control node or a proxy for malicious traffic. As the software lacks robust file path normalization or mandatory file renaming policies upon storage, the attacker maintains significant control over the uploaded asset, allowing for multiple execution attempts without the file being purged or quarantined."
}