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CVE-2021-37698

Missing TLS service certificate validation in GelfWriter, ElasticsearchWriter, InfluxdbWriter and Influxdb2Writer

Published: Aug 19, 2021Updated: Nov 3, 2025 Sources: CVE List NVDCWE-295
NVD MITRE
7.5CVSSHIGH
EPSS Score
1.4%
Top 30.7%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
No Fix Available

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 Breakdown

AV:NAC:LPR:NUI:NS:UC:HI:NA:N
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:NIntegrity
None
A:NAvailability
None
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Weaknesses

CWE-295

Affected Products

icinga2Icinga
On-prem
Enterprise Software / itsm-monitoring
icingaicinga
On-prem
Enterprise Software / itsm-monitoring
debian linuxdebian
On-premOS
Operating Systems / linux-distro
icingaoss-projectUSEnterprise Softwareaka icinga web 2, icinga2, icinga
debianoss-projectGBOperating Systemsaka debian gnu/linux

Attack Graph

Products CVE Techniques Tactics

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Exploitability

No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.

MITRE ATT&CK

1 technique
Collection
View detailed technique mapping

References

https://github.com/Icinga/icinga2/security/advisories/GHSA-cxfm-8j5v-5qr2
github.com
https://github.com/Icinga/icinga2/releases/tag/v2.11.11
github.com
https://github.com/Icinga/icinga2/releases/tag/v2.12.6
github.com
and 3 more references View all →

Timeline

Published
Aug 19, 2021
Last Updated
Nov 3, 2025

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