CVE-2020-4037

Open Redirect in OAuth2 Proxy

Description

In OAuth2 Proxy from version 5.1.1 and less than version 6.0.0, users can provide a redirect address for the proxy to send the authenticated user to at the end of the authentication flow. This is expected to be the original URL that the user was trying to access. This redirect URL is checked within the proxy and validated before redirecting the user to prevent malicious actors providing redirects to potentially harmful sites. This has been fixed in version 6.0.0.

Category

4.3
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.32%
Third-Party Advisory github.com Third-Party Advisory github.com
Affected: OAuth2 Proxy OAuth2 Proxy
Published at:
Updated at:

References

Link Tags
https://github.com/oauth2-proxy/oauth2-proxy/security/advisories/GHSA-5m6c-jp6f-2vcv third party advisory
https://github.com/oauth2-proxy/oauth2-proxy/commit/ee5662e0f5001d76ec76562bb605abbd07c266a2 third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2020-4037?
CVE-2020-4037 has been scored as a medium severity vulnerability.
How to fix CVE-2020-4037?
To fix CVE-2020-4037, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2020-4037 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2020-4037 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2020-4037?
CVE-2020-4037 affects OAuth2 Proxy OAuth2 Proxy.
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