Fix XSS in service discovery active check output
Summary
| CVE | CVE-2026-9549 |
|---|---|
| State | PUBLISHED |
| Assigner | Checkmk |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-06-08 13:16:34 UTC |
| Updated | 2026-06-08 15:53:09 UTC |
| Description | Stored cross-site scripting in the service discovery active check output in Checkmk <2.5.0p5, <2.4.0p31, <2.3.0p48, and all 2.2.0 versions allows an administrator who can configure active or custom checks to inject malicious HTML or JavaScript into check output that executes in the browser of an admin or a user with host read permissions when they run the check on the service discovery page. |
Risk And Classification
Primary CVSS: v4.0 4.8 MEDIUM from [email protected]
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Problem Types: CWE-79 | CWE-79 CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 4.0 | [email protected] | Secondary | 4.8 | MEDIUM | CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N/E:X/C... |
| 4.0 | CNA | DECLARED | 4.8 | MEDIUM | CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N |
| 3.1 | [email protected] | Primary | 4.8 | MEDIUM | CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N |
CVSS v4.0 Breakdown
Attack Vector
NetworkAttack Complexity
LowAttack Requirements
NonePrivileges Required
HighUser Interaction
PassiveConfidentiality
NoneIntegrity
LowAvailability
NoneSub Conf.
NoneSub Integrity
LowSub Availability
NoneCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
LowPrivileges Required
HighUser Interaction
RequiredScope
ChangedConfidentiality
LowIntegrity
LowAvailability
NoneCVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N
NVD Known Affected Configurations (CPE 2.3)
| Type | Vendor | Product | Version | Update | Edition | Language |
|---|---|---|---|---|---|---|
| Application | Checkmk | Checkmk | 2.2.0 | - | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | b1 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | b2 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | b3 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | b4 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | b5 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | b6 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | b7 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | b8 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | i1 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p1 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p10 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p11 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p12 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p13 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p14 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p15 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p16 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p17 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p18 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p19 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p2 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p20 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p21 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p22 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p23 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p24 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p25 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p26 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p27 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p28 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p29 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p3 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p30 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p31 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p32 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p33 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p34 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p35 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p36 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p37 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p38 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p39 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p4 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p40 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p41 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p42 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p43 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p44 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p45 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p46 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p47 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p5 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p6 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p7 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p8 | All | All |
| Application | Checkmk | Checkmk | 2.2.0 | p9 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | - | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | b1 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | b2 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | b3 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | b4 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | b5 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | b6 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p1 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p10 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p11 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p12 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p13 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p14 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p15 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p16 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p17 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p18 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p19 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p2 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p20 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p21 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p22 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p23 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p24 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p25 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p26 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p27 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p28 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p29 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p3 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p30 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p31 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p32 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p33 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p34 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p35 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p36 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p37 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p38 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p39 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p4 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p40 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p41 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p42 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p43 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p44 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p45 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p46 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p47 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p5 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p6 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p7 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p8 | All | All |
| Application | Checkmk | Checkmk | 2.3.0 | p9 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | All | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | - | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | b1 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | b2 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | b3 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | b4 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | b5 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | b6 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | p1 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | p10 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | p11 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | p12 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | p13 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | p14 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | p15 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | p16 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | p17 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | p18 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | p19 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | p2 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | p20 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | p21 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | p22 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | p23 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | p24 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | p25 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | p26 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | p27 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | p28 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | p29 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | p3 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | p30 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | p4 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | p5 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | p6 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | p7 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | p8 | All | All |
| Application | Checkmk | Checkmk | 2.4.0 | p9 | All | All |
| Application | Checkmk | Checkmk | 2.5.0 | - | All | All |
| Application | Checkmk | Checkmk | 2.5.0 | b1 | All | All |
| Application | Checkmk | Checkmk | 2.5.0 | b2 | All | All |
| Application | Checkmk | Checkmk | 2.5.0 | b3 | All | All |
| Application | Checkmk | Checkmk | 2.5.0 | p1 | All | All |
| Application | Checkmk | Checkmk | 2.5.0 | p2 | All | All |
| Application | Checkmk | Checkmk | 2.5.0 | p3 | All | All |
| Application | Checkmk | Checkmk | 2.5.0 | p4 | All | All |
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Checkmk GmbH | Checkmk | affected 2.5.0 2.5.0p5 semver | Not specified |
| CNA | Checkmk GmbH | Checkmk | affected 2.4.0 2.4.0p31 semver | Not specified |
| CNA | Checkmk GmbH | Checkmk | affected 2.3.0 2.3.0p48 semver | Not specified |
| CNA | Checkmk GmbH | Checkmk | affected 2.2.0 semver | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| checkmk.com/werk/17993 | [email protected] | checkmk.com | Vendor Advisory |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.