CVE-2023-35943

Public Exploit
Envoy vulnerable to CORS filter segfault when origin header is removed

Description

Envoy is an open source edge and service proxy designed for cloud-native applications. Prior to versions 1.27.0, 1.26.4, 1.25.9, 1.24.10, and 1.23.12, the CORS filter will segfault and crash Envoy when the `origin` header is removed and deleted between `decodeHeaders`and `encodeHeaders`. Versions 1.27.0, 1.26.4, 1.25.9, 1.24.10, and 1.23.12 have a fix for this issue. As a workaround, do not remove the `origin` header in the Envoy configuration.

Category

6.3
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.01%
Third-Party Advisory github.com
Affected: envoyproxy envoy
Published at:
Updated at:

References

Link Tags
https://github.com/envoyproxy/envoy/security/advisories/GHSA-mc6h-6j9x-v3gq third party advisory exploit

Frequently Asked Questions

What is the severity of CVE-2023-35943?
CVE-2023-35943 has been scored as a medium severity vulnerability.
How to fix CVE-2023-35943?
To fix CVE-2023-35943, 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-2023-35943 being actively exploited in the wild?
It is possible that CVE-2023-35943 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-2023-35943?
CVE-2023-35943 affects envoyproxy envoy.
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