CVE-2026-92984 in Hubzero
Summary
by MITRE • 09/17/2026
HUBzero CMS through 2.2.32 accepts session identifiers from query strings and request variables instead of cookies alone, allowing unauthenticated attackers to fixate victim sessions. Attackers can obtain a valid session identifier, send victims a crafted link containing it, and replay the identifier after the victim authenticates to hijack their account and access.
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Analysis
by VulDB Data Team • 09/17/2026
The vulnerability identified in HUBzero CMS versions through 2.2.32 represents a critical flaw in session management architecture that fundamentally undermines the security of user authentication mechanisms. The core technical issue stems from the application's permissive handling of session identifiers, specifically its acceptance of these tokens via query string parameters and request variables rather than restricting them exclusively to secure HTTP cookies. This design choice deviates significantly from established best practices for web application security, where session IDs should be transmitted only through opaque, HttpOnly, and Secure cookie attributes to prevent interception or manipulation by client-side scripts or external entities. By allowing the session identifier to be passed as a URL parameter or form variable, the system exposes itself to several classes of attacks that rely on the predictability or controllability of these tokens by malicious actors.
This architectural weakness directly facilitates session fixation attacks, a technique categorized under CWE-384 in the Common Weakness Enumeration framework. In this scenario, an unauthenticated attacker can generate or obtain a valid session identifier and embed it within a crafted URL link. When a victim clicks on this link, their browser sends the pre-determined session ID to the server as part of the HTTP request headers or query parameters. The HUBzero CMS accepts this external input and associates it with the user's subsequent login process. Consequently, when the victim authenticates using valid credentials, the application binds the attacker-controlled session identifier to the authenticated account rather than generating a new, secure session token. This effectively allows the attacker to hijack the victim's active session simply by waiting for them to log in while holding the fixed session ID.
The operational impact of this vulnerability is severe, as it enables unauthorized access to user accounts without requiring password guessing or credential theft. Once the session fixation is successful and the victim authenticates, the attacker can replay the same session identifier from their own browser to gain full administrative privileges or access sensitive data associated with the victim's account. This bypasses multi-factor authentication protections if they are tied strictly to the initial login event rather than continuous session validation. The attack vector requires minimal effort from the adversary, who only needs to lure a target into visiting a malicious link containing the fixed session token. This makes it particularly dangerous in social engineering contexts where users may be tricked into clicking on seemingly legitimate but compromised URLs.
From an offensive security perspective, this vulnerability aligns with MITRE ATT&CK technique T1078, which covers valid accounts and specifically relates to account hijacking through credential or session theft. The lack of proper session regeneration after authentication is a common oversight in legacy content management systems that prioritizes convenience over security. To mitigate this risk, it is imperative to enforce strict cookie-only transmission for all session identifiers by setting the HttpOnly flag to prevent access via JavaScript and the Secure flag to ensure transmission only occurs over encrypted HTTPS connections. Furthermore, developers must implement server-side validation that rejects any session IDs provided through query strings or POST data, ensuring that sessions are exclusively managed through secure cookies. Additionally, implementing automatic session regeneration upon successful authentication is a critical defense-in-depth measure that invalidates pre-login session tokens and assigns new ones post-authentication, thereby neutralizing the fixation attack vector entirely.