CVE-2026-70309 Microsoft Edge (Chromium-based) Security Feature Bypass Vulnerability
An origin validation error in Microsoft Edge allows attackers to bypass security features over the network.
- 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-2026-70309?
CVE-2026-70309 is a medium-severity vulnerability in Microsoft Edge Chromium, published on 28 Aug 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
Origin validation error in Microsoft Edge (Chromium-based) allows an unauthorized attacker to bypass a security feature over a network.
Weakness: CWE-346
Which versions are affected by CVE-2026-70309?
It affects 1 product.
Products include Microsoft Edge Chromium.
How do I fix CVE-2026-70309?
No fix has been published for CVE-2026-70309 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-70309 being exploited?
There is no known exploitation of CVE-2026-70309 in the wild and no public exploit code.
Other vulnerabilities in Microsoft Edge Chromium
- CVE-2024-21326 Microsoft Edge (Chromium-based) Elevation of Privilege Vulnerability
- CVE-2023-35618 Microsoft Edge (Chromium-based) Elevation of Privilege Vulnerability
- CVE-2023-36735 Microsoft Edge (Chromium-based) Elevation of Privilege Vulnerability
- CVE-2022-33649 Microsoft Edge (Chromium-based) Security Feature Bypass Vulnerability
- CVE-2026-58289 Microsoft Edge (Chromium-based) Remote Code Execution Vulnerability
Sources
Also known as GHSA-j3c8-38vp-j837.