# 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.

- **Severity:** Medium 6.1 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N`)
- **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 available:** No
- **Published:** 29 Apr 2026
- **Updated:** 29 Apr 2026
- **Also known as:** GHSA-6pqq-8j74-wgg5

## 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 (Improper Neutralization of Input During Web Page Generation)

## Which versions are affected by CVE-2025-10503?

It affects 1 product.


Products: 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.

## 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](https://insights.sbomify.com/CVE-2016-4311/): Cross-site request forgery in n/a (high 8.8)
- [CVE-2025-10470](https://insights.sbomify.com/CVE-2025-10470/): Denial-of-Service via Magic Link Authentication in WSO2 Identity Server Allows Service Unavailability (high 8.6)
- [CVE-2025-12107](https://insights.sbomify.com/CVE-2025-12107/): Server-Side Template Injection via Velocity Template Engine in Multiple WSO2 Products Allows Remote Code Execution (high 8.4)
- [CVE-2016-4312](https://insights.sbomify.com/CVE-2016-4312/): XML external entity in n/a (high 7.5)
- [CVE-2025-10908](https://insights.sbomify.com/CVE-2025-10908/): Account Lock Bypass via Magic Link or Pass Key Authentication in WSO2 Identity Server Allows Unauthorized Access (high 7.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-10503 and fix it if it is affected.

What it is: 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.
Exploitation: There is no known exploitation of CVE-2025-10503 in the wild and no public exploit code.

Affected product: Wso2 Identity Server. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2025-10503/ (Markdown: https://insights.sbomify.com/CVE-2025-10503/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-10503
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-10503
- OSV: https://osv.dev/vulnerability/CVE-2025-10503

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-10503/
Summaries are generated and may contain mistakes; the official description above is the record.