Using techniques that built on the slipstream research, a malicious webpage could have scanned both an internal network's hosts as well as services running on the user's local machine utilizing WebRTC connections. This vulnerability affects Firefox ESR < 78.9, Firefox < 87, and Thunderbird < 78.9.
https://www.mozilla.org/security/advisories/mfsa2021-11/
https://www.mozilla.org/security/advisories/mfsa2021-12/
Source: MITRE
Published: 2021-03-31
Updated: 2021-08-06
Type: CWE-326
Base Score: 4.3
Vector: AV:N/AC:M/Au:N/C:N/I:P/A:N
Impact Score: 2.9
Exploitability Score: 8.6
Severity: MEDIUM
Base Score: 6.5
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
Impact Score: 3.6
Exploitability Score: 2.8
Severity: MEDIUM