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CVE-2026-61551: CWE-674: Uncontrolled Recursion in Icinga icinga2

0
High
VulnerabilityCVE-2026-61551cvecve-2026-61551cwe-674
Published: 09/18/2026 (09/18/2026, 17:23:11 UTC)
Source: CVE Database V5
Vendor/Project: Icinga
Product: icinga2

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.

CVSS v3.1

Score 8.6high

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
Low
Availability
High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H

Affected software

Icinga

icinga2

Affected versions
<2.14.9>=2.15.0 <2.15.4>=2.16.0 <2.16.2
GitHub Actionsmore threats →ai
icinga/icinga2
pkg:github/icinga/icinga2
Affected versions
<2.14.9>=2.15.0 <2.15.4>=2.16.0 <2.16.2

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AI-Powered Analysis

Machine-generated threat intelligence

AILast updated: 09/18/2026, 17:47:42 UTC

Technical Analysis

CVE-2026-61551 is a vulnerability in Icinga 2's JSON parser where deeply nested JSON input leads to uncontrolled recursion, exhausting the call stack. This vulnerability is reachable by unauthenticated network clients via the Icinga 2 service on TCP port 5665. The flaw allows remote attackers to crash the Icinga 2 process, resulting in denial of service. There is no evidence of remote code execution. The vulnerability is addressed in versions 2.14.9, 2.15.4, and 2.16.2.

Potential Impact

Remote unauthenticated attackers can cause a denial of service by crashing the Icinga 2 process through sending deeply nested JSON payloads. Confidentiality and integrity impacts are rated low, while availability impact is high. No known exploits in the wild or code execution have been reported.

Mitigation Recommendations

Upgrade Icinga 2 to version 2.14.9, 2.15.4, or 2.16.2 or later, where this vulnerability is fixed. No other mitigation is indicated or required.

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Technical Details

Data Version
5.2
Assigner Short Name
GitHub_M
Date Reserved
2026-07-10T16:48:39.922Z
Cvss Version
3.1
State
PUBLISHED

Threat ID: 6aad759d55bf5e2cf54f30a4

Added to database: 09/18/2026, 17:32:13 UTC

Last enriched: 09/18/2026, 17:47:42 UTC

Last updated: 09/18/2026, 22:12:51 UTC

Views: 5

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