If a valid external protocol handler was referenced in an image tag, the resulting broken image size could be distinguished from a broken image size of a non-existent protocol handler. This allowed an attacker to successfully probe whether an external protocol handler was registered. This vulnerability affects Firefox < 82.
{ "availability": "No subscription required", "binaries": [ { "binary_version": "82.0+build2-0ubuntu0.16.04.5", "binary_name": "firefox" }, { "binary_version": "82.0+build2-0ubuntu0.16.04.5", "binary_name": "firefox-dev" }, { "binary_version": "82.0+build2-0ubuntu0.16.04.5", "binary_name": "firefox-geckodriver" }, { "binary_version": "82.0+build2-0ubuntu0.16.04.5", "binary_name": "firefox-mozsymbols" } ] }
{ "availability": "No subscription required", "binaries": [ { "binary_version": "82.0+build2-0ubuntu0.18.04.1", "binary_name": "firefox" }, { "binary_version": "82.0+build2-0ubuntu0.18.04.1", "binary_name": "firefox-dev" }, { "binary_version": "82.0+build2-0ubuntu0.18.04.1", "binary_name": "firefox-geckodriver" }, { "binary_version": "82.0+build2-0ubuntu0.18.04.1", "binary_name": "firefox-mozsymbols" } ] }
{ "availability": "No subscription required", "binaries": [ { "binary_version": "82.0+build2-0ubuntu0.20.04.1", "binary_name": "firefox" }, { "binary_version": "82.0+build2-0ubuntu0.20.04.1", "binary_name": "firefox-dev" }, { "binary_version": "82.0+build2-0ubuntu0.20.04.1", "binary_name": "firefox-geckodriver" }, { "binary_version": "82.0+build2-0ubuntu0.20.04.1", "binary_name": "firefox-mozsymbols" } ] }