Description

Unauthenticated Cross Site Scripting (XSS) in Events Manager <= 7.4.1 versions.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "7.1",
  "pubDate": "2026-08-06T15:17:20.590Z",
  "pubdate": "2026-08-06T15:17:20.590Z",
  "executiveSummary": "An unauthenticated Cross-Site Scripting (XSS) vulnerability has been identified in the Events Manager plugin, specifically affecting versions 7.4.1 and prior. This security flaw enables remote, unauthenticated threat actors to inject arbitrary malicious client-side scripts, typically JavaScript, into vulnerable parameters processed and rendered by the application. The primary impact of this vulnerability includes potential session hijacking, unauthorized access to sensitive user data, credential theft, and defacement or redirection of affected web pages when interacting with a victim's browser context.\nThe affected product is the Events Manager plugin operating on vulnerable versions <= 7.4.1. Risk implications are critical for sites utilizing the affected software, as malicious payloads can be executed within the security context of an administrator or regular user viewing the manipulated event data. Exploitation requires network access to the target web application and relies on tricking a user into executing the payload or processing improperly sanitized inputs rendered by the vulnerable component. No prior authentication or privileged access is required by the attacker to inject the payload, significantly lowering the attack complexity and barrier to entry for malicious actors.",
  "technicalDetails": "The vulnerability stems from improper input sanitization and output encoding within the Events Manager plugin for versions <= 7.4.1. Specifically, the root cause lies in the application's failure to adequately validate, sanitize, or escape user-supplied parameters before reflecting them back in the HyperText Markup Language (HTML) response or storing them for later rendering in the Document Object Model (DOM).\nBecause the vulnerability is unauthenticated, an attacker does not require any prior system credentials or special user privileges to interact with the vulnerable component. Network exposure is external, allowing any remote user with HTTP/HTTPS access to the target web application to transmit crafted inputs containing malicious script payloads directly to the vulnerable application endpoints.\nThe attack flow proceeds as follows: First, the attacker crafts a malicious Uniform Resource Locator (URL) or an HTTP request containing malicious JavaScript payloads embedded within vulnerable input fields handled by Events Manager. Second, the unauthenticated request is sent to the web server hosting the vulnerable plugin. Third, the application processes the request and improperly embeds the unsupplied, unsanitized payload into the server response or database storage without applying context-aware output encoding. Fourth, when a victim accesses the affected page or triggers the rendering of the malicious event data, the browser parses the response and executes the injected script within the security context of the victim's session.\nThe payload behavior involves executing arbitrary JavaScript in the victim's browser session. This can lead to post-exploitation impacts such as stealing session cookies, capturing keystrokes, performing unauthorized actions on behalf of the authenticated user, or defacing the victim's view of the web application. The affected component involves the request handling and rendering logic of the Events Manager plugin where user input is dynamically outputted without adequate defensive sanitization controls."
}