CVE-2024-23647

PKCE downgrade attack in Authentik

Description

Authentik is an open-source Identity Provider. There is a bug in our implementation of PKCE that allows an attacker to circumvent the protection that PKCE offers. PKCE adds the code_challenge parameter to the authorization request and adds the code_verifier parameter to the token request. Prior to 2023.8.7 and 2023.10.7, a downgrade scenario is possible: if the attacker removes the code_challenge parameter from the authorization request, authentik will not do the PKCE check. Because of this bug, an attacker can circumvent the protection PKCE offers, such as CSRF attacks and code injection attacks. Versions 2023.8.7 and 2023.10.7 fix the issue.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.07%
Third-Party Advisory github.com
Affected: goauthentik authentik
Published at:
Updated at:

References

Link Tags
https://github.com/goauthentik/authentik/security/advisories/GHSA-mrx3-gxjx-hjqj third party advisory
https://github.com/goauthentik/authentik/commit/38e04ae12720e5d81b4f7ac77997eb8d1275d31a patch

Frequently Asked Questions

What is the severity of CVE-2024-23647?
CVE-2024-23647 has been scored as a medium severity vulnerability.
How to fix CVE-2024-23647?
To fix CVE-2024-23647, 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-2024-23647 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2024-23647 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-2024-23647?
CVE-2024-23647 affects goauthentik authentik.
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