CVE-2026-61551 json
Icinga 2: Stack overflow via deeply nested JSON objects
published 4mo ago modified last mo. also EUVD-2026-83209 , GHSA-wh38-wg57-5w7g
Unreviewed: the maintainers' own advisory
Published by the maintainers on their GitHub repository Icinga/icinga2. GitHub has not reviewed it into the GitHub Advisory Database, so the affected packages and versions are the maintainers' word. Read the full advisory on GitHub.
- cvss
- 8.6
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.9%
- EPSS 0.9% chance of exploitation in 30 days, percentile 61%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- icinga icinga 2.14.9, 2.15.4, 2.16.2
- icinga2 Debian 13 2.14.6-1+deb13u1
- icinga2 Debian 14 2.16.2-1
debian advisories DEBIAN-CVE-2026-61551
- github.com/Icinga/icinga2@391504e commit
- github.com/Icinga/icinga2@3d9166f commit
- github.com/Icinga/icinga2@4964d24 commit
- github.com/Icinga/icinga2@ed163a8 commit
- github.com/Icinga/icinga2#10908 pull request
- github.com/Icinga/icinga2/releases/tag/v2.14.9 release
- github.com/Icinga/icinga2/releases/tag/v2.15.4 release
- github.com/Icinga/icinga2/releases/tag/v2.16.2 release
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- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- last mo.
Exploit prediction
0.94% chance of exploitation in the next 30 days, higher than 61% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 8.6 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H |
Affected products
- Icinga icinga2
Classification
- Weakness
-
- CWE-674 Uncontrolled Recursion
References
- github.com /Icinga/icinga2/pull/10908
- github.com /Icinga/icinga2/commit/391504eaa9ed9aee81f84008c57ec821974b74ee
- github.com /Icinga/icinga2/commit/3d9166ff52ff1a64a286c39af57957d63442c137
- github.com /Icinga/icinga2/commit/4964d2444ca5c4fae9036054554e1c6e0025fb89
- github.com /Icinga/icinga2/commit/ed163a8aa9d296820dd2ad14c47bf3f6a3fcce7d
-
github.com
/Icinga/icinga2/security/advisories/GHSA-wh38-wg57-5w7g
advisory
- github.com /Icinga/icinga2/releases/tag/v2.14.9
- github.com /Icinga/icinga2/releases/tag/v2.15.4
- github.com /Icinga/icinga2/releases/tag/v2.16.2
- icinga.com /blog/icinga2-security-release-v2-16-2
Sources
- CVE List CVE-2026-61551
- NVD CVE-2026-61551
- Maintainer advisory GHSA-wh38-wg57-5w7g
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
The maintainers of Icinga/icinga2 published their own advisory on GitHub. Reviewed sources take precedence over it.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.