High severity · published Aug 19, 2021
CVE-2021-37698
Icinga is a monitoring system which checks the availability of network resources, notifies users of outages, and generates performance data for reporting
7.5
CVSS
1.4%
EPSS
No
On KEV
Description
Icinga is a monitoring system which checks the availability of network resources, notifies users of outages, and generates performance data for reporting. In versions 2.5.0 through 2.13.0, ElasticsearchWriter, GelfWriter, InfluxdbWriter and Influxdb2Writer do not verify the server's certificate despite a certificate authority being specified. Icinga 2 instances which connect to any of the mentioned time series databases (TSDBs) using TLS over a spoofable infrastructure should immediately upgrade to version 2.13.1, 2.12.6, or 2.11.11 to patch the issue. Such instances should also change the credentials (if any) used by the TSDB writer feature to authenticate against the TSDB. There are no workarounds aside from upgrading.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.4% · higher than 72% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
9.0 · source: NVD
IC
Icinga · Icinga
2.5.0 before 2.11.10; 2.12.0 before 2.12.6; 2.13.0 before 2.13.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-37698
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-37698
Release Notes
https://github.com/Icinga/icinga2/releases/tag/v2.11.11
Release Notes
https://github.com/Icinga/icinga2/releases/tag/v2.12.6
Release Notes
https://github.com/Icinga/icinga2/releases/tag/v2.13.1
Third Party Advisory
https://github.com/Icinga/icinga2/security/advisories/GHSA-cxfm-8j5v-5qr2
Mailing List
https://lists.debian.org/debian-lts-announce/2021/11/msg00010.html
lists.debian.org
https://lists.debian.org/debian-lts-announce/2024/11/msg00010.html
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