Vulnerability · Published Jul 15, 2021 · Assigned by GitHub_M

CVE-2021-32739Results of queries for ApiListener objects include the ticket salt which allows in turn to steal (more privileged) identities

High 8.8

In plain English

A high-severity security flaw in icinga2 from Icinga. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.1% (higher than 67% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)8.8High
Exploit odds (30 days)1.1%top 33.2% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known

Official description

Icinga is a monitoring system which checks the availability of network resources, notifies users of outages, and generates performance data for reporting. From version 2.4.0 through version 2.12.4, a vulnerability exists that may allow privilege escalation for authenticated API users. With a read-ony user's credentials, an attacker can view most attributes of all config objects including `ticket_salt` of `ApiListener`. This salt is enough to compute a ticket for every possible common name (CN). A ticket, the master node's certificate, and a self-signed certificate are enough to successfully request the desired certificate from Icinga. That certificate may in turn be used to steal an endpoint or API user's identity. Versions 2.12.5 and 2.11.10 both contain a fix the vulnerability. As a workaround, one may either specify queryable types explicitly or filter out ApiListener objects.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Debian:12icinga22.12.5-1DEBIAN-CVE-2021-32739
Debian:13icinga22.12.5-1DEBIAN-CVE-2021-32739
Debian:14icinga22.12.5-1DEBIAN-CVE-2021-32739
Ubuntu:22.04:LTSicinga2no fix listedUBUNTU-CVE-2021-32739
Ubuntu:24.04:LTSicinga2no fix listedUBUNTU-CVE-2021-32739
Ubuntu:25.10icinga2no fix listedUBUNTU-CVE-2021-32739
Ubuntu:26.04:LTSicinga2no fix listedUBUNTU-CVE-2021-32739
Ubuntu:26.10icinga2no fix listedUBUNTU-CVE-2021-32739

Affected products (as reported)

VendorProductVersions
Icinga icinga2 >= 2.4.0, <= 2.12.4

Weakness: CWE-267 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

References