CVE-2024-49672 identifies a security vulnerability in the Google Docs RSVP plugin developed by giffordcheung, specifically versions up to and including 2.0.1. The vulnerability is a Cross-Site Request Forgery (CSRF) flaw that enables attackers to trick authenticated users into submitting unwanted requests to the application. This CSRF vulnerability leads to Stored Cross-Site Scripting (XSS), where malicious scripts injected by the attacker are permanently stored within the application’s data, such as guest lists or RSVP entries. When other users access the infected data, the malicious scripts execute in their browsers, potentially stealing session tokens, manipulating content, or performing actions on behalf of the user. The combination of CSRF and stored XSS significantly increases the attack surface, as CSRF can be used to inject the persistent XSS payload without the victim’s explicit consent. The vulnerability affects the Google Docs RSVP plugin, a tool that integrates with Google Docs to manage event guest lists and RSVPs, widely used in organizational and event management contexts. No CVSS score has been assigned yet, and no official patches or exploit reports are currently available, indicating the vulnerability is newly disclosed. The vulnerability was published on October 29, 2024, and was reserved earlier that month. The absence of patches means users of the plugin remain exposed until mitigations or updates are released.

The exploitation of this vulnerability can have severe consequences for organizations using the Google Docs RSVP plugin. Attackers can leverage CSRF to inject stored XSS payloads, leading to persistent malicious scripts executing in the context of users’ browsers. This can result in theft of authentication tokens, unauthorized actions performed on behalf of users, data manipulation, and potential spread of malware. The confidentiality of sensitive event and guest information can be compromised, while the integrity of RSVP data can be altered, undermining trust and operational reliability. Availability could be affected if attackers use the vulnerability to disrupt service or cause application errors. Organizations relying on this plugin for event management or collaboration may face reputational damage, data breaches, and compliance issues. Since the vulnerability requires the victim to be authenticated but no additional user interaction beyond visiting a malicious page is needed, the attack vector is relatively easy to exploit in environments where users are logged in. The lack of known exploits in the wild provides a window for proactive mitigation, but the risk remains significant given the nature of the vulnerability.

To mitigate this vulnerability, organizations should immediately review their use of the Google Docs RSVP plugin and consider disabling it until a patched version is available. Implementing strict anti-CSRF tokens and validating the origin of requests within the plugin’s codebase is critical to prevent unauthorized request forgery. Input sanitization and output encoding should be enforced rigorously to eliminate stored XSS risks. Administrators should monitor event guest lists and related data for suspicious or unexpected entries that could indicate exploitation attempts. Employing Content Security Policy (CSP) headers can help reduce the impact of XSS by restricting script execution sources. User education about phishing and suspicious links can reduce the likelihood of users visiting malicious pages that trigger CSRF attacks. Regularly checking for updates from the plugin developer and applying patches promptly once available is essential. Additionally, organizations should audit their Google Workspace environment for any unusual activity related to the plugin and consider implementing multi-factor authentication to limit session hijacking risks.