Vulnerability in Mozilla Firefox

CVE-2020-26967

When listening for page changes with a Mutation Observer, a malicious web page could confuse Firefox Screenshots into interacting with elements other than those that it injected into the page. This would lead to internal errors and unexpected behavior in the Screenshots code. This vulnerability affects Firefox < 83.

EPSS: 0.008 (54.2th 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-2020-26967?
CVE-2020-26967 is a medium-severity vulnerability in Mozilla Firefox. CVSS score: 6.5/10. Published 2020-12-09.
How severe is CVE-2020-26967?
Medium severity. CVSS v3 base score is 6.5 out of 10.