Improper Certificate Validation in Icinga - CVE-2021-37698
Published: August 19, 2021 / Updated: June 29, 2026
Vulnerability identifier: #VU135832
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2021-37698
CWE-ID: CWE-295
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Icinga
Affected software:
Icinga
Icinga
Detailed vulnerability description
The vulnerability allows a remote attacker to intercept sensitive information.
The vulnerability exists due to improper certificate validation in ElasticsearchWriter, GelfWriter, InfluxdbWriter, and Influxdb2Writer when establishing TLS connections to configured TSDB servers. A remote attacker can present a spoofed certificate to intercept sensitive information.
Exploitation requires a spoofable network infrastructure between the affected instance and the target TSDB service.
How to mitigate CVE-2021-37698
Install security update from vendor's website.