CVE-2021-21291: OAuth2 Proxy is an open-source reverse proxy and static file server that provides authentication using Providers (Google, GitHub, and others) to validate…

PriorityP427medium6.1CVSS 3.1

AVNACLPRNUIRSCCLILAN

EPSS

1.35%

68.1th percentile

OAuth2 Proxy is an open-source reverse proxy and static file server that provides authentication using Providers (Google, GitHub, and others) to validate accounts by email, domain or group. In OAuth2 Proxy before version 7.0.0, for users that use the whitelist domain feature, a domain that ended in a similar way to the intended domain could have been allowed as a redirect. For example, if a whitelist domain was configured for ".example.com", the intention is that subdomains of example.com are allowed. Instead, "example.com" and "badexample.com" could also match. This is fixed in version 7.0.0 onwards. As a workaround, one can disable the whitelist domain feature and run separate OAuth2 Proxy instances for each subdomain.

Affected

4 ranges

Vendor	Product	Version range	Fixed in
github.com	oauth2-proxy_oauth2-proxy	0 – 3.2.0	—
github.com	oauth2-proxy_oauth2-proxy_v7	>= 0 < 7.0.0	7.0.0
oauth2-proxy	oauth2-proxy	< 7.0.0	7.0.0
oauth2_proxy_project	oauth2_proxy	< 7.0.0	7.0.0

CVSS provenance

nvdv3.16.1MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

nvdv2.05.8MEDIUMAV:N/AC:M/Au:N/C:P/I:P/A:N

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