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 6.5 MEDIUM
CVSS v2.0 4.3 MEDIUM

6.5^/10

CVSS v3 : 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://bugzilla.mozilla.org/show_bug.cgi?id=1672528	Issue Tracking Permissions Required Vendor Advisory
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

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2020-12-09 01:15

Updated : 2020-12-10 18:20

NVD link : CVE-2020-26961

Mitre link : CVE-2020-26961

CVE.ORG link : CVE-2020-26961

JSON object : View

Products Affected

mozilla

thunderbird
firefox
firefox_esr

CWE

NVD-CWE-noinfo

{"id": "CVE-2020-26961", "cveTags": [], "metrics": {"cvssMetricV2": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"version": "2.0", "baseScore": 4.3, "accessVector": "NETWORK", "vectorString": "AV:N/AC:M/Au:N/C:N/I:P/A:N", "authentication": "NONE", "integrityImpact": "PARTIAL", "accessComplexity": "MEDIUM", "availabilityImpact": "NONE", "confidentialityImpact": "NONE"}, "acInsufInfo": false, "impactScore": 2.9, "baseSeverity": "MEDIUM", "obtainAllPrivilege": false, "exploitabilityScore": 8.6, "obtainUserPrivilege": false, "obtainOtherPrivilege": false, "userInteractionRequired": true}], "cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 6.5, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N", "integrityImpact": "HIGH", "userInteraction": "REQUIRED", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "NONE"}, "impactScore": 3.6, "exploitabilityScore": 2.8}]}, "published": "2020-12-09T01:15:13.283", "references": [{"url": "https://bugzilla.mozilla.org/show_bug.cgi?id=1672528", "tags": ["Issue Tracking", "Permissions Required", "Vendor Advisory"], "source": "security@mozilla.org"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2020-50/", "tags": ["Vendor Advisory"], "source": "security@mozilla.org"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2020-51/", "tags": ["Vendor Advisory"], "source": "security@mozilla.org"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2020-52/", "tags": ["Vendor Advisory"], "source": "security@mozilla.org"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "NVD-CWE-noinfo"}]}], "descriptions": [{"lang": "en", "value": "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."}, {"lang": "es", "value": "Cuando un DNS sobre HTTPS est\u00e1 en uso, intencionalmente filtra el RFC1918 y los rangos de IP relacionados con las respuestas, ya que no tiene sentido al venir de un resolutor de DoH. Sin embargo, cuando una direcci\u00f3n IPv4 fue mapeada por medio de IPv6, estas direcciones fueron dejadas pasar err\u00f3neamente, conllevando a un potencial ataque de DNS Rebinding. Esta vulnerabilidad afecta a Firefox versiones anteriores a 83, Firefox ESR versiones anteriores a 78,5 y Thunderbird versiones anteriores a 78,5"}], "lastModified": "2020-12-10T18:20:27.617", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "9385C808-43DD-4D02-B1A9-89A2E3986DF2", "versionEndExcluding": "83.0"}, {"criteria": "cpe:2.3:a:mozilla:firefox_esr:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "36160ED9-05B8-4E38-8C67-49EE1738AF8B", "versionEndExcluding": "78.5"}, {"criteria": "cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "C169EC17-3490-437D-A36B-40C3DE316175", "versionEndExcluding": "78.5"}], "operator": "OR"}]}], "sourceIdentifier": "security@mozilla.org"}