CVE-2023-35944

Public Exploit
Envoy vulnerable to incorrect handling of HTTP requests and responses with mixed case schemes

Description

Envoy is an open source edge and service proxy designed for cloud-native applications. Envoy allows mixed-case schemes in HTTP/2, however, some internal scheme checks are case-sensitive. Prior to versions 1.27.0, 1.26.4, 1.25.9, 1.24.10, and 1.23.12, this can lead to the rejection of requests with mixed-case schemes such as `htTp` or `htTps`, or the bypassing of some requests such as `https` in unencrypted connections. With a fix in versions 1.27.0, 1.26.4, 1.25.9, 1.24.10, and 1.23.12, Envoy will now lowercase scheme values by default, and change the internal scheme checks that were case-sensitive to be case-insensitive. There are no known workarounds for this issue.

Categories

8.2
CVSS
Severity: High
CVSS 3.1 •
EPSS 0.01%
Third-Party Advisory github.com
Affected: envoyproxy envoy
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2023-35944?
CVE-2023-35944 has been scored as a high severity vulnerability.
How to fix CVE-2023-35944?
To fix CVE-2023-35944, 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-2023-35944 being actively exploited in the wild?
It is possible that CVE-2023-35944 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-2023-35944?
CVE-2023-35944 affects envoyproxy envoy.
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