CVE-2026-92068 Site isolation issue in the Reader Mode component
A site isolation flaw in Reader Mode allows bypassing security boundaries, requiring users to upgrade Firefox or Thunderbird.
- 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
What is CVE-2026-92068?
CVE-2026-92068 is a medium-severity vulnerability in Mozilla Firefox, published on 15 Sep 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
Site isolation issue in the Reader Mode component. This vulnerability was fixed in Firefox 156, Firefox ESR 153.3, Thunderbird 156, and Thunderbird 153.3.
Weakness: CWE-346
Which versions are affected by CVE-2026-92068?
It affects 2 products.
Products include Mozilla Firefox, Mozilla Thunderbird.
How do I fix CVE-2026-92068?
Upgrade to a fixed version.
Is CVE-2026-92068 being exploited?
There is no known exploitation of CVE-2026-92068 in the wild and no public exploit code.
Other vulnerabilities in Mozilla Firefox
Sources
Also known as DEBIAN-CVE-2026-92068, GHSA-jgrj-mv42-4xrq, UBUNTU-CVE-2026-92068.