CVE-2020-26961 Affecting firefox-esr package, versions <78.5.0esr-1


Severity

Recommended
0.0
medium
0
10

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Threat Intelligence

EPSS
0.14% (52nd percentile)

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  • Snyk IDSNYK-DEBIAN12-FIREFOXESR-1546458
  • published18 Nov 2020
  • disclosed9 Dec 2020

Introduced: 18 Nov 2020

CVE-2020-26961  (opens in a new tab)

How to fix?

Upgrade Debian:12 firefox-esr to version 78.5.0esr-1 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream firefox-esr package and not the firefox-esr package as distributed by Debian. See How to fix? for Debian:12 relevant fixed versions and status.

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.

CVSS Scores

version 3.1