Description

Unauthenticated Cross Site Scripting (XSS) in Quick Event Manager <= 9.17 versions.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "7.1",
  "pubDate": "2026-09-03T17:17:29.770Z",
  "pubdate": "2026-09-03T17:17:29.770Z",
  "executiveSummary": "Quick Event Manager versions 9.17 and below are susceptible to an unauthenticated Cross-Site Scripting (XSS) vulnerability.\nThis vulnerability allows remote, unauthenticated attackers to inject malicious JavaScript into web pages viewed by other users, including administrative personnel.\nThe flaw stems from insufficient input sanitization of user-supplied data, which is subsequently rendered in the browser without proper context-aware encoding.\nSuccessful exploitation poses a significant security risk, as an attacker can execute arbitrary scripts within the security context of the victim's session.\nPotential impacts include session hijacking, unauthorized actions performed on behalf of the user, credential theft, redirection to malicious websites, and the defacement of the application's interface.\nThe vulnerability is particularly critical due to the lack of required authentication, enabling exploitation by any visitor to the public-facing components of the affected system.\nOrganizations utilizing Quick Event Manager are advised to identify the vulnerable installations and apply appropriate security controls to mitigate unauthorized script execution.",
  "technicalDetails": "The vulnerability identified in Quick Event Manager (version 9.17 and earlier) manifests as an unauthenticated Cross-Site Scripting (XSS) flaw, specifically characterized by the failure of the application to properly sanitize and validate input parameters before embedding them into the HTTP response.\nRoot Cause: The root cause lies in the application's handling of user-controllable input via HTTP GET or POST parameters that are reflected directly back to the client side. The affected component fails to perform adequate output encoding or context-aware sanitization, allowing for the injection of arbitrary HTML tags and JavaScript event handlers (such as 'onerror' or 'onload') into the generated DOM.\nAttack Flow: An attacker initiates the exploitation by crafting a malicious URL containing a payload within a vulnerable parameter. This URL is then distributed to a target user, which may include an application administrator. When the target user accesses the specially crafted URL, the web server processes the request and incorporates the malicious payload directly into the HTML response document.\nExecution Context: Once the server delivers the response, the victim's browser interprets the injected payload as legitimate source code from the trusted domain. Because the script executes within the security context of the victim's current session, the attacker inherits the victim's privileges. This allows the attacker to bypass Same-Origin Policy (SOP) restrictions, facilitating the access of sensitive data such as session cookies, CSRF tokens, or locally stored information.\nExploitation Requirements: The attack requires no authentication or specialized privileges, as the entry point is exposed to the public network. The only requirement is that the victim must interact with the malicious input, which is frequently achieved through social engineering or by embedding the malicious link on a third-party site. The vulnerability affects the client-side rendering process, specifically where user data is outputted without escaping characters such as '<', '>', and '&'.\nPost-Exploitation: Upon successful script execution, an attacker may perform various malicious actions, including: 1) Session Hijacking: Stealing session identifiers to impersonate the user. 2) Unauthorized Actions: Submitting web forms or triggering administrative functions by performing authenticated background requests (e.g., AJAX). 3) Phishing: Modifying the DOM to present fake login forms to harvest credentials. 4) Malware Distribution: Redirecting users to external sites hosting malicious software."
}