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.
CVSS Details
- CVSS 3.1 Base Score: 5.3
- CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Alpine Linux | alpine-linux-upgrade-firefoxalpine-linux-upgrade-librewolf | Aug 22, 2024 | Oct 22, 2020 | |
| Arch Linux | arch-linux-upgrade-latest | Jul 11, 2025 | Oct 22, 2020 | |
| Mfsa2020 45 | mozilla-firefox-upgrade-82_0 | Oct 21, 2020 | Oct 20, 2020 | |
| Ubuntu | ubuntu-upgrade-firefox | Mar 22, 2023 | Oct 22, 2020 |
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