Vulnerability in Mozilla Firefox

CVE-2020-26976

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.

EPSS: 0.016 (72.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N.

Affected products

References

Frequently asked questions

What is CVE-2020-26976?
CVE-2020-26976 is a medium-severity vulnerability in Mozilla Firefox. CVSS score: 6.5/10. Published 2021-01-07.
How severe is CVE-2020-26976?
Medium severity. CVSS v3 base score is 6.5 out of 10.