CVE-2021-21323

Brave is an open source web browser with a focus on privacy and security. In Brave versions 1.17.73-1.20.103, the CNAME adblocking feature added in Brave 1.17.73 accidentally initiated DNS requests that bypassed the Brave Tor proxy. Users with adblocking enabled would leak DNS requests from Tor windows to their DNS provider. (DNS requests that were not initiated by CNAME adblocking would go through Tor as expected.) This is fixed in Brave version 1.20.108

CVSS v3.0 5.3 MEDIUM
CVSS v2.0 4.3 MEDIUM

5.3^/10

CVSS v3.0 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

4.3^/10

CVSS v2.0 : MEDIUM

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

Exploitability : 8.6 / Impact : 2.9

Access Vector NETWORK

Access Complexity MEDIUM

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact NONE

Availability Impact NONE

References

Link	Resource
https://github.com/brave/brave-browser/issues/13527	Patch Third Party Advisory
https://github.com/brave/brave-core/pull/7769	Patch Third Party Advisory
https://github.com/brave/brave-browser/security/advisories/GHSA-mqjf-9x5g-2rv6	Third Party Advisory
https://github.com/brave/brave-core/commit/12fe321eaad8acc1cbd1d70b4128f687777bcf15	Patch Third Party Advisory
https://hackerone.com/reports/1077022	Permissions Required Third Party Advisory

Advertisement

Configurations

Configuration 1 (hide)

cpe:2.3:a:brave:brave:*:*:*:*:*:*:*:*

Information

Published : 2021-02-23 15:15

Updated : 2021-03-01 08:14

NVD link : CVE-2021-21323

Mitre link : CVE-2021-21323

JSON object : View

CWE

CWE-200

Exposure of Sensitive Information to an Unauthorized Actor

Advertisement

Products Affected

brave

brave

{"cve": {"data_type": "CVE", "references": {"reference_data": [{"url": "https://github.com/brave/brave-browser/issues/13527", "name": "https://github.com/brave/brave-browser/issues/13527", "tags": ["Patch", "Third Party Advisory"], "refsource": "MISC"}, {"url": "https://github.com/brave/brave-core/pull/7769", "name": "https://github.com/brave/brave-core/pull/7769", "tags": ["Patch", "Third Party Advisory"], "refsource": "MISC"}, {"url": "https://github.com/brave/brave-browser/security/advisories/GHSA-mqjf-9x5g-2rv6", "name": "https://github.com/brave/brave-browser/security/advisories/GHSA-mqjf-9x5g-2rv6", "tags": ["Third Party Advisory"], "refsource": "CONFIRM"}, {"url": "https://github.com/brave/brave-core/commit/12fe321eaad8acc1cbd1d70b4128f687777bcf15", "name": "https://github.com/brave/brave-core/commit/12fe321eaad8acc1cbd1d70b4128f687777bcf15", "tags": ["Patch", "Third Party Advisory"], "refsource": "MISC"}, {"url": "https://hackerone.com/reports/1077022", "name": "https://hackerone.com/reports/1077022", "tags": ["Permissions Required", "Third Party Advisory"], "refsource": "MISC"}]}, "data_format": "MITRE", "description": {"description_data": [{"lang": "en", "value": "Brave is an open source web browser with a focus on privacy and security. In Brave versions 1.17.73-1.20.103, the CNAME adblocking feature added in Brave 1.17.73 accidentally initiated DNS requests that bypassed the Brave Tor proxy. Users with adblocking enabled would leak DNS requests from Tor windows to their DNS provider. (DNS requests that were not initiated by CNAME adblocking would go through Tor as expected.) This is fixed in Brave version 1.20.108"}]}, "problemtype": {"problemtype_data": [{"description": [{"lang": "en", "value": "CWE-200"}]}]}, "data_version": "4.0", "CVE_data_meta": {"ID": "CVE-2021-21323", "ASSIGNER": "security-advisories@github.com"}}, "impact": {"baseMetricV2": {"cvssV2": {"version": "2.0", "baseScore": 4.3, "accessVector": "NETWORK", "vectorString": "AV:N/AC:M/Au:N/C:P/I:N/A:N", "authentication": "NONE", "integrityImpact": "NONE", "accessComplexity": "MEDIUM", "availabilityImpact": "NONE", "confidentialityImpact": "PARTIAL"}, "severity": "MEDIUM", "acInsufInfo": false, "impactScore": 2.9, "obtainAllPrivilege": false, "exploitabilityScore": 8.6, "obtainUserPrivilege": false, "obtainOtherPrivilege": false, "userInteractionRequired": false}, "baseMetricV3": {"cvssV3": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.3, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "LOW"}, "impactScore": 1.4, "exploitabilityScore": 3.9}}, "publishedDate": "2021-02-23T23:15Z", "configurations": {"nodes": [{"children": [], "operator": "OR", "cpe_match": [{"cpe23Uri": "cpe:2.3:a:brave:brave:*:*:*:*:*:*:*:*", "cpe_name": [], "vulnerable": true, "versionEndIncluding": "1.20.103", "versionStartIncluding": "1.17.73"}]}], "CVE_data_version": "4.0"}, "lastModifiedDate": "2021-03-01T16:14Z"}