vulnerability
MFSA2020-51 Firefox: Security Vulnerabilities fixed in Firefox ESR 78.5 (CVE-2020-26961)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 4 | (AV:N/AC:M/Au:N/C:N/I:P/A:N) | Nov 17, 2020 | Nov 18, 2020 | Mar 27, 2026 |
Severity
4
CVSS
(AV:N/AC:M/Au:N/C:N/I:P/A:N)
Published
Nov 17, 2020
Added
Nov 18, 2020
Modified
Mar 27, 2026
Description
When DNS over HTTPS is in use, it intentionally filters RFC1918 and related IP ranges from the responses as these do not make sense coming from a DoH resolver. However when an IPv4 address was mapped through IPv6, these addresses were erroneously let through, leading to a potential DNS Rebinding attack. This vulnerability affects Firefox < 83, Firefox ESR < 78.5, and Thunderbird < 78.5.
Solution
mozilla-firefox-esr-upgrade-78_5
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