CVE-2026-61551
Medium
Elevated severity or exploit probability.
CVSS base
8.6
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H
EPSS — probability of exploitation (30 days)
0.9%
59.3th percentile
CISA KEV
Not listed
Weakness / dates
CWE-674
Published 2026-09-18 · modified 2026-09-18
Description
Icinga 2 is an open source monitoring system. Prior to 2.14.9, 2.15.4, and 2.16.2, parsing deeply nested JSON can exhaust the call stack because nesting depth is not bounded. The affected JSON parsing paths are reachable by unauthenticated network clients through the Icinga 2 service on TCP port 5665, allowing a remote attacker to crash the process, while possible code execution has not been demonstrated. This issue is fixed in versions 2.14.9, 2.15.4, and 2.16.2.
References
- https://github.com/Icinga/icinga2/commit/391504eaa9ed9aee81f84008c57ec821974b74ee
- https://github.com/Icinga/icinga2/commit/3d9166ff52ff1a64a286c39af57957d63442c137
- https://github.com/Icinga/icinga2/commit/4964d2444ca5c4fae9036054554e1c6e0025fb89
- https://github.com/Icinga/icinga2/commit/ed163a8aa9d296820dd2ad14c47bf3f6a3fcce7d
- https://github.com/Icinga/icinga2/pull/10908
- https://github.com/Icinga/icinga2/releases/tag/v2.14.9
- https://github.com/Icinga/icinga2/releases/tag/v2.15.4
- https://github.com/Icinga/icinga2/releases/tag/v2.16.2
- https://github.com/Icinga/icinga2/security/advisories/GHSA-wh38-wg57-5w7g
- https://icinga.com/blog/icinga2-security-release-v2-16-2