{"id":"UBUNTU-CVE-2020-26967","details":"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 \u003c 83.","modified":"2026-01-30T02:19:25.612115Z","published":"2020-11-17T00:00:00Z","related":["USN-4637-1","USN-4637-2"],"upstream":["CVE-2020-26967"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2020-26967"},{"type":"REPORT","url":"https://www.mozilla.org/en-US/security/advisories/mfsa2020-50/#CVE-2020-26967"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-4637-1"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-4637-2"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2020-26967"}],"affected":[{"package":{"name":"firefox","ecosystem":"Ubuntu:16.04:LTS","purl":"pkg:deb/ubuntu/firefox@83.0+build2-0ubuntu0.16.04.3?arch=source&distro=xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"83.0+build2-0ubuntu0.16.04.3"}]}],"versions":["41.0.2+build2-0ubuntu1","42.0+build2-0ubuntu1","44.0+build3-0ubuntu2","44.0.1+build1-0ubuntu1","44.0.2+build1-0ubuntu1","45.0+build2-0ubuntu1","45.0.1+build1-0ubuntu1","45.0.2+build1-0ubuntu1","46.0+build5-0ubuntu0.16.04.2","46.0.1+build1-0ubuntu0.16.04.2","47.0+build3-0ubuntu0.16.04.1","48.0+build2-0ubuntu0.16.04.1","49.0+build4-0ubuntu0.16.04.1","49.0.2+build2-0ubuntu0.16.04.2","50.0+build2-0ubuntu0.16.04.2","50.0.2+build1-0ubuntu0.16.04.1","50.1.0+build2-0ubuntu0.16.04.1","51.0.1+build2-0ubuntu0.16.04.1","51.0.1+build2-0ubuntu0.16.04.2","52.0+build2-0ubuntu0.16.04.1","52.0.1+build2-0ubuntu0.16.04.1","52.0.2+build1-0ubuntu0.16.04.1","53.0+build6-0ubuntu0.16.04.1","53.0.2+build1-0ubuntu0.16.04.2","53.0.3+build1-0ubuntu0.16.04.2","54.0+build3-0ubuntu0.16.04.1","55.0.1+build2-0ubuntu0.16.04.2","55.0.2+build1-0ubuntu0.16.04.1","56.0+build6-0ubuntu0.16.04.1","56.0+build6-0ubuntu0.16.04.2","57.0+build4-0ubuntu0.16.04.5","57.0+build4-0ubuntu0.16.04.6","57.0.1+build2-0ubuntu0.16.04.1","57.0.3+build1-0ubuntu0.16.04.1","57.0.4+build1-0ubuntu0.16.04.1","58.0+build6-0ubuntu0.16.04.1","58.0.1+build1-0ubuntu0.16.04.1","58.0.2+build1-0ubuntu0.16.04.1","59.0+build5-0ubuntu0.16.04.1","59.0.1+build1-0ubuntu0.16.04.1","59.0.2+build1-0ubuntu0.16.04.1","59.0.2+build1-0ubuntu0.16.04.3","60.0+build2-0ubuntu0.16.04.1","60.0.1+build2-0ubuntu0.16.04.1","60.0.2+build1-0ubuntu0.16.04.1","61.0+build3-0ubuntu0.16.04.2","61.0.1+build1-0ubuntu0.16.04.1","62.0+build2-0ubuntu0.16.04.3","62.0+build2-0ubuntu0.16.04.4","62.0+build2-0ubuntu0.16.04.5","62.0.3+build1-0ubuntu0.16.04.2","63.0+build2-0ubuntu0.16.04.2","63.0.3+build1-0ubuntu0.16.04.1","64.0+build3-0ubuntu0.16.04.1","65.0+build2-0ubuntu0.16.04.1","65.0.1+build2-0ubuntu0.16.04.1","66.0+build3-0ubuntu0.16.04.2","66.0.1+build1-0ubuntu0.16.04.1","66.0.2+build1-0ubuntu0.16.04.1","66.0.3+build1-0ubuntu0.16.04.1","66.0.4+build3-0ubuntu0.16.04.1","66.0.5+build1-0ubuntu0.16.04.1","67.0+build2-0ubuntu0.16.04.1","67.0.1+build1-0ubuntu0.16.04.1","67.0.2+build2-0ubuntu0.16.04.1","67.0.3+build1-0ubuntu0.16.04.1","67.0.4+build1-0ubuntu0.16.04.1","68.0+build3-0ubuntu0.16.04.1","68.0.1+build1-0ubuntu0.16.04.1","68.0.2+build1-0ubuntu0.16.04.1","69.0+build2-0ubuntu0.16.04.4","69.0.1+build1-0ubuntu0.16.04.1","69.0.2+build1-0ubuntu0.16.04.1","70.0+build2-0ubuntu0.16.04.1","70.0.1+build1-0ubuntu0.16.04.1","71.0+build5-0ubuntu0.16.04.1","72.0.1+build1-0ubuntu0.16.04.1","72.0.2+build1-0ubuntu0.16.04.1","73.0.1+build1-0ubuntu0.16.04.1","74.0+build3-0ubuntu0.16.04.1","74.0.1+build1-0ubuntu0.16.04.1","75.0+build3-0ubuntu0.16.04.1","76.0+build2-0ubuntu0.16.04.1","76.0.1+build1-0ubuntu0.16.04.1","77.0.1+build1-0ubuntu0.16.04.1","78.0.1+build1-0ubuntu0.16.04.1","78.0.2+build2-0ubuntu0.16.04.1","79.0+build1-0ubuntu0.16.04.2","80.0+build2-0ubuntu0.16.04.1","80.0.1+build1-0ubuntu0.16.04.1","81.0+build2-0ubuntu0.16.04.1","81.0.2+build1-0ubuntu0.16.04.1","82.0+build2-0ubuntu0.16.04.5","82.0.2+build1-0ubuntu0.16.04.1","82.0.3+build1-0ubuntu0.16.04.1"],"ecosystem_specific":{"availability":"No 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