Cyber Resilience

CVE-2021-32739

HighPublic PoC

Published: 15 July 2021

Published
15 July 2021
Modified
03 November 2025
KEV Added
Patch
CVSS Score v3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0030 53.4th percentile
Risk Priority 18 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-32739 is a high-severity Privilege Defined With Unsafe Actions (CWE-267) vulnerability in Icinga Icinga. Its CVSS base score is 8.8 (High).

Operationally, ranked in the top 46.6% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability details

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.…

more

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.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

icinga
icinga
2.4.0 — 2.11.10 · 2.12.0 — 2.12.5
debian
debian linux
9.0

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-269

Policy addresses roles, responsibilities, and privilege management to prevent improper privilege assignments.

addresses: CWE-269

Access supervision ensures privileges are assigned and managed without improper escalation or retention.

addresses: CWE-269

Assigning group/role memberships and access authorizations (privileges) while reviewing accounts addresses improper privilege management.

addresses: CWE-269

Enforces proper privilege management by requiring all decisions through the verified reference monitor.

addresses: CWE-269

By mandating division of duties across roles, the control enforces proper privilege management and prevents a single entity from controlling an entire sensitive process.

addresses: CWE-269

Implements core proper privilege management by restricting to only required rights.

addresses: CWE-269

Policy requires training on privilege management and least privilege, making it harder to exploit improper privilege management weaknesses.

addresses: CWE-269

Training covers proper privilege management practices, making incorrect privilege assignments less likely.

References