CVE-2020-26961

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 v3.0 6.5 MEDIUM
CVSS v2.0 4.3 MEDIUM

6.5^/10

CVSS v3.0 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

4.3^/10

CVSS v2.0 : MEDIUM

Vector : AV:N/AC:M/Au:N/C:N/I:P/A:N

Exploitability : 8.6 / Impact : 2.9

Access Vector NETWORK

Access Complexity MEDIUM

Authentication NONE

Confidentiality Impact NONE

Integrity Impact PARTIAL

Availability Impact NONE

References

Link	Resource
https://www.mozilla.org/security/advisories/mfsa2020-50/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2020-51/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2020-52/	Vendor Advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1672528	Issue Tracking Permissions Required Vendor Advisory

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Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:mozilla:firefox::::::::
	cpe:2.3:a:mozilla:firefox_esr::::::::
	cpe:2.3:a:mozilla:thunderbird::::::::

Information

Published : 2020-12-08 17:15

Updated : 2020-12-10 10:20

NVD link : CVE-2020-26961

Mitre link : CVE-2020-26961

JSON object : View

CWE

NVD-CWE-noinfo

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Products Affected

mozilla

firefox
firefox_esr
thunderbird

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