CVE-2026-33400
Stored XSS in Wallos Payment Rename Enables Session Hijacking
Publication date: 2026-03-24
Last updated on: 2026-03-26
Assigner: GitHub, Inc.
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| wallosapp | wallos | to 4.7.0 (exc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-79 | The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
The vulnerability exists in Wallos, an open-source personal subscription tracker, prior to version 4.7.0. It is a stored cross-site scripting (XSS) flaw in the payment method rename endpoint. This allows any authenticated user to inject arbitrary JavaScript code that executes when any user visits certain pages such as Settings, Subscriptions, or Statistics.
Additionally, because the authentication cookie (wallos_login) lacks the HttpOnly flag, the injected JavaScript can hijack user sessions by stealing this cookie.
This vulnerability has been fixed in version 4.7.0.
How can this vulnerability impact me? :
This vulnerability can lead to full session hijacking for users of Wallos. An attacker who is authenticated can inject malicious JavaScript that executes in other users' browsers, potentially stealing their session cookies and gaining unauthorized access to their accounts.
Such unauthorized access could allow attackers to view or manipulate personal subscription data or other sensitive information accessible through the application.
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
I don't know
How can this vulnerability be detected on my network or system? Can you suggest some commands?
I don't know
What immediate steps should I take to mitigate this vulnerability?
To mitigate this vulnerability, you should upgrade Wallos to version 4.7.0 or later, where the stored cross-site scripting (XSS) issue in the payment method rename endpoint has been patched.
Additionally, ensure that the wallos_login authentication cookie is set with the HttpOnly flag to prevent session hijacking.