CVE-2020-26976 Security feature bypass in Firefox
A service worker could intercept requests for secure pages embedded in insecure iframes, bypassing secure context restrictions in Firefox.
- 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-2020-26976?
CVE-2020-26976 is a medium-severity vulnerability in Debian Debian Linux, published on 7 Jan 2021. 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
When a HTTPS pages was embedded in a HTTP page, and there was a service worker registered for the former, the service worker could have intercepted the request for the secure page despite the iframe not being a secure context due to the (insecure) framing. This vulnerability affects Firefox < 84.
Which versions are affected by CVE-2020-26976?
It affects 2 products.
Products include Debian Debian Linux, Mozilla Firefox.
How do I fix CVE-2020-26976?
Upgrade to a fixed version.
Is CVE-2020-26976 being exploited?
There is no known exploitation of CVE-2020-26976 in the wild and no public exploit code.
Other vulnerabilities in Debian Debian Linux
Sources
Also known as DEBIAN-CVE-2020-26976, GHSA-77q8-crvw-8w9q, UBUNTU-CVE-2020-26976.