Description

A vulnerability was determined in cym1102 nginxWebUI up to 4.4.2. This issue affects the function MainController.autoUpdate of the file /adminPage/main/autoUpdate. This manipulation of the argument url causes code injection. Remote exploitation of the attack is possible. The exploit has been publicly disclosed and may be utilized. The pull request to fix this issue awaits acceptance.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "6.3",
  "pubDate": "2026-09-13T20:16:51.487Z",
  "pubdate": "2026-09-13T20:16:51.487Z",
  "executiveSummary": "A critical code injection vulnerability has been identified in cym1102 nginxWebUI, impacting all versions up to and including 4.4.2.\nThe vulnerability resides within the MainController.autoUpdate function, which improperly sanitizes user-supplied input via the 'url' argument.\nSuccessful exploitation allows a remote, unauthenticated attacker to execute arbitrary code on the underlying host system.\nGiven the nature of the application—frequently deployed with administrative privileges to manage Nginx services—the impact is severe, potentially leading to full system compromise.\nThe vulnerability is publicly disclosed, significantly elevating the risk of exploitation by malicious actors.\nOrganizations using affected versions are at high risk, as no official patch has been merged or finalized at this time.",
  "technicalDetails": "The vulnerability is categorized as a code injection flaw located in the /adminPage/main/autoUpdate endpoint of the cym1102 nginxWebUI application.\nThe root cause is the insecure handling of the 'url' parameter passed to the MainController.autoUpdate function. The application fails to perform adequate input validation or sanitization before processing this parameter, which is likely utilized to fetch or execute remote resources for software updates.\nAn attacker can exploit this by crafting a malicious URL that points to a payload under their control. By manipulating the 'url' argument, the attacker can force the server-side application to interact with a malicious source or directly inject command sequences that are subsequently interpreted and executed by the host operating system or the application runtime environment.\nThe exploitation flow typically begins with a remote attacker sending a specially crafted HTTP request to the vulnerable endpoint. Because the application logic passes this unsanitized input to an underlying execution sink, the injection point allows for the redirection of the update mechanism to an arbitrary file or command string.\nSince the application is designed to manage web server configurations, the process executing this function often runs with elevated privileges, such as root or the web server user. Successful execution results in the attainment of remote code execution (RCE) capabilities, granting the attacker control over the server process.\nPost-exploitation activities are not limited to system configuration manipulation; the attacker can leverage the compromised instance to pivot into the internal network, exfiltrate sensitive Nginx configuration files, TLS certificates, or deploy persistence mechanisms such as web shells.\nThe vulnerability is present in versions up to 4.4.2. As the software interacts with system-level services, the remote exploitation vector is particularly dangerous for exposed management interfaces.\nWhile a pull request has been submitted to address the flaw, it currently awaits acceptance, meaning all instances running version 4.4.2 or earlier remain inherently insecure."
}