CVE-2026-37503 Cross-site scripting in n/a
An admin can inject JavaScript via theme configuration, allowing attackers to steal cookies or hijack sessions of all site visitors.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-37503?
CVE-2026-37503 is a medium-severity cross-site scripting vulnerability in n/a, published on 1 May 2026. An attacker needs administrator access to exploit it, and only if a user opens a file or follows a link.
Official description
Cross-Site Scripting (XSS) in V2Board thru 1.7.4. The custom_html field in theme configuration is rendered using Blade unescaped output in public/theme/v2board/dashboard.blade.php. An admin can inject arbitrary JavaScript via the saveThemeConfig API. All site visitors execute the payload, enabling cookie theft, session hijacking, or phishing.
Weakness: CWE-79
Which versions are affected by CVE-2026-37503?
It affects 1 product.
Products include V2board V2board.
How do I fix CVE-2026-37503?
No fix has been published for CVE-2026-37503 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-2026-37503 being exploited?
There is no known exploitation of CVE-2026-37503 in the wild and no public exploit code.
Other vulnerabilities in n/a
Sources
Also known as GHSA-4jxj-79x3-676q.