CVE-2023-27493

Public Exploit
Envoy doesn't escape HTTP header values

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, Envoy does not sanitize or escape request properties when generating request headers. This can lead to characters that are illegal in header values to be sent to the upstream service. In the worst case, it can cause upstream service to interpret the original request as two pipelined requests, possibly bypassing the intent of Envoy’s security policy. Versions 1.26.0, 1.25.3, 1.24.4, 1.23.6, and 1.22.9 contain a patch. As a workaround, disable adding request headers based on the downstream request properties, such as downstream certificate properties.

Categories

8.1
CVSS
Severity: High
CVSS 3.1 •
EPSS 0.01%
Vendor Advisory github.com
Affected: envoyproxy envoy
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2023-27493?
CVE-2023-27493 has been scored as a high severity vulnerability.
How to fix CVE-2023-27493?
To fix CVE-2023-27493, 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-2023-27493 being actively exploited in the wild?
It is possible that CVE-2023-27493 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-2023-27493?
CVE-2023-27493 affects envoyproxy envoy.
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