CVE-2020-26961
6.5
MEDIUM
CVSS 3.1
EPSS 0.27%
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.
How to fix CVE-2020-26961
To remediate CVE-2020-26961, upgrade the affected package to a fixed version below.
- —upgrade to 78.5.0esr-1 or later
- —upgrade to 1:78.5.0-1 or later
Is CVE-2020-26961 being exploited?
Low — EPSS is 0.3%, meaning exploitation activity has not been observed at scale.
Affected packages (2)
- from 0, < 78.5.0esr-1
- from 0, < 1:78.5.0-1
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | MEDIUM6.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N |