CVE-2026-42838 Microsoft Edge (Chromium-based) Elevation of Privilege Vulnerability

Medium 5.4 Published 12 May 2026 Updated 10 Aug 2026

An attacker can elevate privileges via injection in Microsoft Edge, requiring a patch to mitigate the risk.

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-2026-42838?

CVE-2026-42838 is a medium-severity code injection vulnerability in Microsoft Edge Chromium, published on 12 May 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

Improper neutralization of special elements in output used by a downstream component ('injection') in Microsoft Edge (Chromium-based) allows an unauthorized attacker to elevate privileges over a network.

Weakness: CWE-74

Which versions are affected by CVE-2026-42838?

It affects 1 product.

Products include Microsoft Edge Chromium.

How do I fix CVE-2026-42838?

No fix has been published for CVE-2026-42838 yet. Limit exposure of the affected software until one is available.

Upgrade, and never evaluate templates, expressions or code built from user input. More about Code injection.

Is CVE-2026-42838 being exploited?

There is no known exploitation of CVE-2026-42838 in the wild and no public exploit code.

All Microsoft Edge Chromium vulnerabilities

Sources

Also known as GHSA-f8cw-8gm3-gpm3.