CVE-2023-27493 : Security Advisory and Response
CVE-2023-27493 impacts Envoy with input validation issues in HTTP headers. Learn about the risk and how to mitigate this vulnerability. Update Envoy versions to ensure system security.
This CVE impacts Envoy due to improper input validation in HTTP header values. The vulnerability exists in versions prior to 1.26.0, 1.25.3, 1.24.4, 1.23.6, and 1.22.9, potentially allowing malicious actors to manipulate request headers.
Understanding CVE-2023-27493
This section provides an insight into the nature of the CVE-2023-27493 vulnerability in Envoy.
What is CVE-2023-27493?
CVE-2023-27493 highlights a flaw in Envoy where it fails to sanitize or escape request properties in generating request headers. This oversight can result in illegal characters being sent to the upstream service, potentially causing misinterpretation of the original request.
The Impact of CVE-2023-27493
The vulnerability's impact includes a risk of upstream services misinterpreting requests as two pipelined requests, which could potentially bypass Envoy's security policy and lead to unauthorized access or data exposure.
Technical Details of CVE-2023-27493
Delve deeper into the technical aspects of CVE-2023-27493 and how it affects systems running Envoy.
Vulnerability Description
The vulnerability stems from Envoy's failure to properly handle request properties in generating request headers, leaving room for malicious manipulation and potential misinterpretation by upstream services.
Affected Systems and Versions
Envoy versions ranging from 1.22.9 to 1.25.0 are affected by this vulnerability, with versions 1.26.0, 1.25.3, 1.24.4, 1.23.6, and 1.22.9 having patches available to address the issue.
Exploitation Mechanism
Exploiting CVE-2023-27493 involves crafting requests with malicious request properties to deceive Envoy and potentially compromise the security of the upstream services.
Mitigation and Prevention
Understand the steps you can take to mitigate the risks associated with CVE-2023-27493 and prevent potential exploits.
Immediate Steps to Take
As an immediate measure, consider disabling the addition of request headers based on downstream request properties to reduce the risk of exploitation until the necessary patches can be applied.
Long-Term Security Practices
Implement stringent input validation protocols and regularly update Envoy to the latest patched versions to ensure ongoing protection against vulnerabilities like CVE-2023-27493.
Patching and Updates
Ensure that affected Envoy versions are promptly updated to versions 1.26.0, 1.25.3, 1.24.4, 1.23.6, or 1.22.9 to address the vulnerability and safeguard system integrity and security.