CVE-2025-5769 in API Control Plane
Summary
by MITRE • 11/03/2026
The authentication endpoint does not properly encode user-supplied input before rendering it within the web page. This lack of output encoding allows an attacker to inject malicious JavaScript payloads into the authentication flow, which are then executed by the victim's browser.
By exploiting this vulnerability, an attacker can redirect the user's browser to a malicious website, modify the content of the web page displayed to the user, or exfiltrate information from the browser. However, due to the implementation of the httpOnly flag on session-related sensitive cookies, session hijacking and similar attacks are not possible.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 11/03/2026
The vulnerability described constitutes a classic Stored Cross-Site Scripting (XSS) flaw located within an authentication endpoint. This specific type of weakness arises from a failure to properly sanitize or encode user-supplied input before it is rendered back into the web page context. In this scenario, the application treats untrusted data as executable code rather than plain text, allowing malicious scripts to be embedded directly into the HTML response. When another user visits the affected authentication flow, their browser parses and executes the injected script within the security context of the vulnerable site. This behavior aligns with CWE-79, which defines Improper Neutralization of Input During Web Page Generation as a critical input validation failure that leads to code injection attacks.
The operational impact of this vulnerability is significant because it occurs at an authentication endpoint, a high-value target for attackers seeking to compromise user accounts or steal sensitive data. An attacker can craft payloads that redirect the victim's browser to malicious websites designed to phish credentials or distribute malware. Furthermore, the injected script can modify the content displayed on the page, potentially altering login forms to capture keystrokes or displaying deceptive messages that trick users into revealing personal information. The ability to exfiltrate data from the browser context means that any non-sensitive but valuable information accessible via JavaScript APIs, such as local storage contents or DOM elements containing user details, can be stolen and sent to an attacker-controlled server. This aligns with MITRE ATT&CK technique T1059, specifically sub-techniques related to command and script interpreters like JavaScript execution within a browser environment.
Despite the severity of this vulnerability, there is a notable mitigation in place regarding session security. The implementation of the httpOnly flag on sensitive cookies effectively prevents client-side scripts from accessing these specific cookie values through standard Document Object Model (DOM) APIs. This configuration ensures that even if an attacker successfully executes arbitrary JavaScript within the victim's browser context, they cannot directly read or manipulate the session identifiers stored in those protected cookies. Consequently, traditional session hijacking attacks, where an adversary steals a valid session token to impersonate the user, are mitigated by this defense-in-depth measure. However, it is important to note that while direct cookie theft is blocked, other attack vectors such as cross-site request forgery (CSRF) or UI redressing remain potential risks if additional protections like anti-CSRF tokens are not also implemented.
To remediate this vulnerability, developers must implement strict output encoding for all user-supplied data rendered in the HTML context of the authentication endpoint. This involves using context-aware encoding libraries that correctly escape special characters based on where they appear within the document structure, such as inside HTML body text, attributes, or JavaScript blocks. Additionally, adopting a Content Security Policy (CSP) can provide an additional layer of defense by restricting the sources from which scripts are allowed to execute, thereby mitigating the impact of any successfully injected payloads. Regular security testing and code reviews focusing on input validation and output encoding practices are essential to prevent similar injection flaws in other parts of the application architecture.