CVE-2023-27496

Public Exploit
Envoy may crash when a redirect url without a state param is received in the oauth filter

Description

Envoy is an open source edge and service proxy designed for cloud-native applications. Prior to versions 1.26.0, 1.25.3, 1.24.4, 1.23.6, and 1.22.9, the OAuth filter assumes that a `state` query param is present on any response that looks like an OAuth redirect response. Sending it a request with the URI path equivalent to the redirect path, without the `state` parameter, will lead to abnormal termination of Envoy process. Versions 1.26.0, 1.25.3, 1.24.4, 1.23.6, and 1.22.9 contain a patch. The issue can also be mitigated by locking down OAuth traffic, disabling the filter, or by filtering traffic before it reaches the OAuth filter (e.g. via a lua script).

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.03%
Vendor Advisory github.com
Affected: envoyproxy envoy
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2023-27496?
CVE-2023-27496 has been scored as a medium severity vulnerability.
How to fix CVE-2023-27496?
To fix CVE-2023-27496, 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-2023-27496 being actively exploited in the wild?
It is possible that CVE-2023-27496 is being exploited or will be exploited in a near future based on public information. 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-2023-27496?
CVE-2023-27496 affects envoyproxy envoy.
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