CVE-2026-90990
📛 CVE Title
Livestatus injection via monitoring filter values
Description
Improper neutralization of newlines in filter values in the monitoring host and service list APIs in Checkmk <2.5.0p14 allows an authenticated user to inject additional Livestatus query headers, bypassing object visibility restrictions in count queries to infer information about hosts and services outside their contact groups and occupying web server and Livestatus workers for an attacker-controlled duration.
Overview
- State
- PUBLISHED
- Assigner (CNA)
- Checkmk
- CVSS severity
- MEDIUM
- CVSS score
- 5.3 / 10
- CVSS vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N- Effective score
- 5.3 / 10 MEDIUM source: CNA overview
- CWE(s)
-
CWE-93 - Reserved
- 2026-09-14
- Published
- 2026-09-22 10:43 UTC
- Last updated
- 2026-09-22 13:04 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/90xxx/CVE-2026-90990.json
NVD triage scoring NVD CVE 2.0
Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.
- NVD published
- 2026-09-22 11:17:25 UTC
- NVD last modified
- 2026-09-22 14:17:17 UTC
NVD / KEV / EPSS data refreshed 2026-09-23 02:33 UTC. Re-run the 🛰 Backfill from NVD button above to refresh.
European Union Vulnerability Database ENISA EUVD
ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.
- EUVD ID
-
EUVD-2026-84350 - Assigner
- Checkmk
- Published
- Sep 22, 2026, 10:43:28 AM
- Updated
- Sep 22, 2026, 1:04:48 PM
- EUVD base score (CVSS 4.0)
-
5.3 / 10
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N - EUVD-reported EPSS
- 0.0000
- Vendors
- Checkmk GmbH
- Products
-
Checkmk (2.5.0 <2.5.0p14)
- Aliases
-
GHSA-v742-5hjw-gqcp
ENISA description: Improper neutralization of newlines in filter values in the monitoring host and service list APIs in Checkmk <2.5.0p14 allows an authenticated user to inject additional Livestatus query headers, bypassing object visibility restrictions in count queries to infer information about hosts and services outside their contact groups and occupying web server and Livestatus workers for an attacker-controlled duration.
EUVD references (1)
Affected products (1)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| Checkmk GmbH | Checkmk |
2.5.0 (affected)
|
— |
Vendor references (1)
References embedded in the original CVE record by the assigning CNA.
- https://checkmk.com/werk/19604 vendor-advisory
Web references (0)
DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.
No web references attached yet.
NVD-tagged references (1)
Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.
- https://checkmk.com/werk/19604 security@checkmk.com
Remediations (10)
-
web:sec.cloudapps.cisco.com
On September 16, 2026 , the Cisco Product Security Incident Response Team (PSIRT) published the advisories that are listed in the following tables. To remediate these vulnerabilities, Cisco strongly recommends that customers upgrade to the fixed software that is indicated in the advisories. For more information about changes in Cisco PSIRT vulnerability disclosure, see Strengthening the ...
2026-09-23 15:41 UTC -
web:securityvulnerability.io
What is CVE-2026-90990 ? In Checkmk versions prior to 2.5.0p14, a vulnerability was identified that allows authenticated users to improperly manipulate filter values in the monitoring host and service list APIs.
2026-09-23 15:41 UTC -
web:senserva.com
Every Microsoft security patch (KB) and the CVEs it fixes, with severity, CVSS, and CISA KEV status. Cross-linked to the CVE reference.
2026-09-23 15:41 UTC -
web:support.microsoft.com
This Hotpatch update for Windows 11, version 25H2 and 24H2 (KB5079420), improves functionality, performance, and reliability. To learn more about differences between security updates, optional non-security preview updates, out-of-band (OOB) updates, and continuous innovation, see Windows monthly updates explained. For information on Windows update terminology, see the different types of ...
2026-09-23 15:41 UTC -
web:support.sap.com
SAP security Patch Day Bulletin This post shares the information on security notes that remediate vulnerabilities discovered in SAP products. SAP strongly recommends that the customer visits the support portal and applies patches on priority to protect their SAP landscape. On 12 th of May 2026 , SAP security patch day saw the release of 15 new security notes.
2026-09-23 15:41 UTC -
web:support.sap.com
SAP Security Patch Day Bulletin This post shares the information on security notes that remediate vulnerabilities discovered in SAP products. SAP strongly recommends that the customer visits the support portal and applies patches on priority to protect their SAP landscape. On 8 th of September 2026 , SAP security patch day saw the release of 19 new security notes. There is 1 update to ...
2026-09-23 15:41 UTC -
web:www.cisecurity.org
<p>Multiple vulnerabilities have been discovered in Microsoft products, the most severe of which could allow for remote code execution. Successful exploitation of the most severe of these vulnerabilities could result in an attacker gaining the same privileges as the logged-on user. Depending on the privileges associated with the user, an attacker could then install programs; view, change, or ...
2026-09-23 15:41 UTC -
web:www.oracle.com
This Critical Patch Update contains 1448 new security patches across the product families listed below. Please note that a My Oracle Support (MOS) note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at July 2026 Critical Patch Update: Executive Summary and Analysis.
2026-09-23 15:41 UTC -
web:www.rapid7.com
CVE-2026-90990 : Checkmk GmbH Checkmk: Improper neutralization of newlines in filter values in the monitoring host and service list APIs in Checkmk <2.5.0p14…. View severity, references, and remediation details from Rapid7.
2026-09-23 15:41 UTC -
web:zecurit.com
Get the complete breakdown of Microsoft's September 2026 Patch Tuesday. We analyze the latest security updates and all critical CVEs .
2026-09-23 15:41 UTC
AI Forensic Analysis
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Raw JSON
The full cvelistV5 record. Download as CVE-2026-90990.json.
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