Beats, Elastic Agent, APM Server, and Fleet Server Improper Certificate Validation issue (ESA-2023-16)
It was discovered that when acting as TLS clients, Beats, Elastic Agent, APM Server, and Fleet Server did not verify whether the server certificate is valid for the target IP address; however, certificate signature validation is still performed. More specifically, when the client is configured to connect to an IP address (instead of a hostname) it does not validate the server certificate's IP SAN values against that IP address and certificate validation fails, and therefore the connection is not blocked as expected.
Affected Versions:
Beats, Elastic Agent, and Fleet Server versions 8.0.0 to 8.9.2
Solutions and Mitigations:
The issue is resolved in version 8.10.1.
CVSSv3: 5.9 (Medium) CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
CVE ID: CVE-2023-31421