CVE-2021-45884

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 3.1% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2021-12-27 · updated 2026-06-17
Weakness: CWE-200

Description

In Brave Desktop 1.17 through 1.33 before 1.33.106, when CNAME-based adblocking and a proxying extension with a SOCKS fallback are enabled, additional DNS requests are issued outside of the proxying extension using the system's DNS settings, resulting in information disclosure. NOTE: this issue exists because of an incomplete fix for CVE-2021-21323 and CVE-2021-22916.

Affected products

https://github.com/brave/brave-core: from 1.17.1 through 1.33.106

References

https://github.com/brave/brave-browser/issues/19070
https://github.com/brave/brave-browser/issues/20079
https://github.com/brave/brave-core/pull/10742
https://hackerone.com/reports/1377864
https://github.com/brave/brave-browser/issues/19070
https://github.com/brave/brave-browser/issues/20079
https://github.com/brave/brave-core/pull/10742
https://hackerone.com/reports/1377864

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