CVE-2026-34416 OSCAL-GUI Reflected XSS via project parameter in oscal.php
Unauthenticated attackers can execute arbitrary JavaScript in victims' browsers via a malicious URL in OSCAL-GUI.
- 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-2026-34416?
CVE-2026-34416 is a medium-severity cross-site scripting vulnerability in brian-ruf OSCAL-GUI, published on 9 Jun 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
OSCAL-GUI contains a reflected cross-site scripting vulnerability that allows unauthenticated attackers to execute arbitrary JavaScript in a victim's browser by injecting malicious input through the project request parameter. Attackers can craft a malicious URL containing unsanitized input that breaks out of the JavaScript string and HTML attribute context in the body onload event handler to execute arbitrary scripts when the link is visited by a victim.
Weakness: CWE-79
Which versions are affected by CVE-2026-34416?
How do I fix CVE-2026-34416?
No fix has been published for CVE-2026-34416 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-2026-34416 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-34416 exists.
Sources
Also known as GHSA-6cgq-85j5-m2j8.