CVE-2026-116861 in Flexible Chat Plugin
Summary
by MITRE • 10/30/2026
Unauthenticated Sensitive Data Exposure in Flexible Chat <= 1.1.0 versions.
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Analysis
by VulDB Data Team • 10/30/2026
The vulnerability identified as an unauthenticated sensitive data exposure within the Flexible Chat application, specifically affecting versions up to and including 1.1.0, represents a critical failure in access control mechanisms that allows attackers to retrieve confidential information without valid credentials. This type of flaw typically stems from improper implementation of authentication checks on API endpoints or server-side functions responsible for handling user-specific data such as chat logs, personal profiles, contact lists, or session tokens. In many modern mobile and web applications, developers may inadvertently expose internal APIs that are intended to be accessed only by authenticated users, assuming that the client application will enforce these restrictions. However, since HTTP requests can be crafted independently of the official client interface, an attacker can directly query these endpoints using tools like curl or specialized vulnerability scanners to extract data that was never meant for public consumption.
From a technical perspective, this flaw aligns with CWE-200: Information Exposure and is often categorized under CWE-862: Missing Authorization in the Common Weakness Enumeration database. The root cause usually involves server-side logic that fails to verify whether the incoming request originates from an authenticated session or possesses valid authorization headers before processing data retrieval requests. In some cases, this may also involve insecure direct object references where sequential identifiers are used for user records without additional validation checks, allowing attackers to iterate through IDs and harvest data belonging to other users. This lack of proper access control creates a significant security gap that undermines the confidentiality guarantees expected by end-users and application administrators alike.
The operational impact of this vulnerability is severe, as it can lead to the mass exfiltration of personally identifiable information including names, email addresses, phone numbers, private messages, and potentially authentication tokens if they are stored in accessible fields. Such data leakage not only violates privacy regulations such as GDPR or CCPA but also facilitates further attacks like social engineering, phishing campaigns, and account takeover attempts using harvested credentials or session cookies. For businesses relying on Flexible Chat for internal communication or customer support, this exposure can result in reputational damage, legal liabilities, and loss of trust among stakeholders who expect their communications to remain private and secure within the platform boundaries.
To mitigate this risk, developers must implement robust authentication and authorization checks at every level where sensitive data is accessed. This includes ensuring that all API endpoints require valid session tokens or JWTs with appropriate expiration times and verifying user permissions before returning any response. Input validation should be enforced to prevent enumeration attacks via sequential IDs by using non-sequential identifiers such as UUIDs instead of integers. Additionally, implementing rate limiting on authentication-related endpoints can help detect and block automated scraping attempts. Regular security audits, penetration testing focused on access control flaws, and adherence to OWASP API Security Top 10 guidelines will significantly reduce the likelihood of similar vulnerabilities being introduced in future updates or maintained within existing codebases until a patched version is deployed by the vendor.