CVE-2025-10503 Reflected Cross-Site Scripting via Authentication Endpoint in WSO2 Identity Server
Attackers can inject malicious scripts via the authentication endpoint to steal data or modify the UI, though session hijacking is prevented by httpOnly cookies.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2025-10503?
CVE-2025-10503 is a medium-severity cross-site scripting vulnerability in Wso2 Identity Server, published on 29 Apr 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
The authentication endpoint accepts user-supplied input without enforcing expected validation constraints, leading to a lack of proper output encoding. This allows for the injection of malicious JavaScript payloads, enabling reflected cross-site scripting.
An attacker can leverage this vulnerability to redirect the user's browser to a malicious website, modify the user interface of the web page, retrieve information from the browser, or cause other harmful actions. However, due to the protection of session-related cookies with the httpOnly flag, session hijacking is not possible.
Weakness: CWE-79
Which versions are affected by CVE-2025-10503?
It affects 1 product.
Products include Wso2 Identity Server.
How do I fix CVE-2025-10503?
No fix has been published for CVE-2025-10503 yet. Limit exposure of the affected software until one is available.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2025-10503 being exploited?
There is no known exploitation of CVE-2025-10503 in the wild and no public exploit code.
Other vulnerabilities in Wso2 Identity Server
- CVE-2016-4311 Cross-site request forgery in n/a
- CVE-2025-10470 Denial-of-Service via Magic Link Authentication in WSO2 Identity Server Allows Service Unavailability
- CVE-2025-12107 Server-Side Template Injection via Velocity Template Engine in Multiple WSO2 Products Allows Remote Code Execution
- CVE-2016-4312 XML external entity in n/a
- CVE-2025-10908 Account Lock Bypass via Magic Link or Pass Key Authentication in WSO2 Identity Server Allows Unauthorized Access
Sources
Also known as GHSA-6pqq-8j74-wgg5.