CVE-2026-9549

June 8, 2026, 3:53 p.m.

4.8
Medium

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.

Product(s) Impacted

Vendor Product Versions
Checkmk
  • Checkmk
  • 2.2.0, 2.3.0, 2.4.0, 2.5.0

Weaknesses

Common security weaknesses mapped to this vulnerability.

CWE-79
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.

*CPE(s)

Affected systems and software identified for this CVE.

Type Vendor Product Version Update Edition Language Software Edition Target Software Target Hardware Other Information
a checkmk checkmk 2.2.0 - / / / / / /
a checkmk checkmk 2.2.0 b1 / / / / / /
a checkmk checkmk 2.2.0 b2 / / / / / /
a checkmk checkmk 2.2.0 b3 / / / / / /
a checkmk checkmk 2.2.0 b4 / / / / / /
a checkmk checkmk 2.2.0 b5 / / / / / /
a checkmk checkmk 2.2.0 b6 / / / / / /
a checkmk checkmk 2.2.0 b7 / / / / / /
a checkmk checkmk 2.2.0 b8 / / / / / /
a checkmk checkmk 2.2.0 i1 / / / / / /
a checkmk checkmk 2.2.0 p1 / / / / / /
a checkmk checkmk 2.2.0 p10 / / / / / /
a checkmk checkmk 2.2.0 p11 / / / / / /
a checkmk checkmk 2.2.0 p12 / / / / / /
a checkmk checkmk 2.2.0 p13 / / / / / /
a checkmk checkmk 2.2.0 p14 / / / / / /
a checkmk checkmk 2.2.0 p15 / / / / / /
a checkmk checkmk 2.2.0 p16 / / / / / /
a checkmk checkmk 2.2.0 p17 / / / / / /
a checkmk checkmk 2.2.0 p18 / / / / / /
a checkmk checkmk 2.2.0 p19 / / / / / /
a checkmk checkmk 2.2.0 p2 / / / / / /
a checkmk checkmk 2.2.0 p20 / / / / / /
a checkmk checkmk 2.2.0 p21 / / / / / /
a checkmk checkmk 2.2.0 p22 / / / / / /
a checkmk checkmk 2.2.0 p23 / / / / / /
a checkmk checkmk 2.2.0 p24 / / / / / /
a checkmk checkmk 2.2.0 p25 / / / / / /
a checkmk checkmk 2.2.0 p26 / / / / / /
a checkmk checkmk 2.2.0 p27 / / / / / /
a checkmk checkmk 2.2.0 p28 / / / / / /
a checkmk checkmk 2.2.0 p29 / / / / / /
a checkmk checkmk 2.2.0 p3 / / / / / /
a checkmk checkmk 2.2.0 p30 / / / / / /
a checkmk checkmk 2.2.0 p31 / / / / / /
a checkmk checkmk 2.2.0 p32 / / / / / /
a checkmk checkmk 2.2.0 p33 / / / / / /
a checkmk checkmk 2.2.0 p34 / / / / / /
a checkmk checkmk 2.2.0 p35 / / / / / /
a checkmk checkmk 2.2.0 p36 / / / / / /
a checkmk checkmk 2.2.0 p37 / / / / / /
a checkmk checkmk 2.2.0 p38 / / / / / /
a checkmk checkmk 2.2.0 p39 / / / / / /
a checkmk checkmk 2.2.0 p4 / / / / / /
a checkmk checkmk 2.2.0 p40 / / / / / /
a checkmk checkmk 2.2.0 p41 / / / / / /
a checkmk checkmk 2.2.0 p42 / / / / / /
a checkmk checkmk 2.2.0 p43 / / / / / /
a checkmk checkmk 2.2.0 p44 / / / / / /
a checkmk checkmk 2.2.0 p45 / / / / / /
a checkmk checkmk 2.2.0 p46 / / / / / /
a checkmk checkmk 2.2.0 p47 / / / / / /
a checkmk checkmk 2.2.0 p5 / / / / / /
a checkmk checkmk 2.2.0 p6 / / / / / /
a checkmk checkmk 2.2.0 p7 / / / / / /
a checkmk checkmk 2.2.0 p8 / / / / / /
a checkmk checkmk 2.2.0 p9 / / / / / /
a checkmk checkmk 2.3.0 - / / / / / /
a checkmk checkmk 2.3.0 b1 / / / / / /
a checkmk checkmk 2.3.0 b2 / / / / / /
a checkmk checkmk 2.3.0 b3 / / / / / /
a checkmk checkmk 2.3.0 b4 / / / / / /
a checkmk checkmk 2.3.0 b5 / / / / / /
a checkmk checkmk 2.3.0 b6 / / / / / /
a checkmk checkmk 2.3.0 p1 / / / / / /
a checkmk checkmk 2.3.0 p10 / / / / / /
a checkmk checkmk 2.3.0 p11 / / / / / /
a checkmk checkmk 2.3.0 p12 / / / / / /
a checkmk checkmk 2.3.0 p13 / / / / / /
a checkmk checkmk 2.3.0 p14 / / / / / /
a checkmk checkmk 2.3.0 p15 / / / / / /
a checkmk checkmk 2.3.0 p16 / / / / / /
a checkmk checkmk 2.3.0 p17 / / / / / /
a checkmk checkmk 2.3.0 p18 / / / / / /
a checkmk checkmk 2.3.0 p19 / / / / / /
a checkmk checkmk 2.3.0 p2 / / / / / /
a checkmk checkmk 2.3.0 p20 / / / / / /
a checkmk checkmk 2.3.0 p21 / / / / / /
a checkmk checkmk 2.3.0 p22 / / / / / /
a checkmk checkmk 2.3.0 p23 / / / / / /
a checkmk checkmk 2.3.0 p24 / / / / / /
a checkmk checkmk 2.3.0 p25 / / / / / /
a checkmk checkmk 2.3.0 p26 / / / / / /
a checkmk checkmk 2.3.0 p27 / / / / / /
a checkmk checkmk 2.3.0 p28 / / / / / /
a checkmk checkmk 2.3.0 p29 / / / / / /
a checkmk checkmk 2.3.0 p3 / / / / / /
a checkmk checkmk 2.3.0 p30 / / / / / /
a checkmk checkmk 2.3.0 p31 / / / / / /
a checkmk checkmk 2.3.0 p32 / / / / / /
a checkmk checkmk 2.3.0 p33 / / / / / /
a checkmk checkmk 2.3.0 p34 / / / / / /
a checkmk checkmk 2.3.0 p35 / / / / / /
a checkmk checkmk 2.3.0 p36 / / / / / /
a checkmk checkmk 2.3.0 p37 / / / / / /
a checkmk checkmk 2.3.0 p38 / / / / / /
a checkmk checkmk 2.3.0 p39 / / / / / /
a checkmk checkmk 2.3.0 p4 / / / / / /
a checkmk checkmk 2.3.0 p40 / / / / / /
a checkmk checkmk 2.3.0 p41 / / / / / /
a checkmk checkmk 2.3.0 p42 / / / / / /
a checkmk checkmk 2.3.0 p43 / / / / / /
a checkmk checkmk 2.3.0 p44 / / / / / /
a checkmk checkmk 2.3.0 p45 / / / / / /
a checkmk checkmk 2.3.0 p46 / / / / / /
a checkmk checkmk 2.3.0 p47 / / / / / /
a checkmk checkmk 2.3.0 p5 / / / / / /
a checkmk checkmk 2.3.0 p6 / / / / / /
a checkmk checkmk 2.3.0 p7 / / / / / /
a checkmk checkmk 2.3.0 p8 / / / / / /
a checkmk checkmk 2.3.0 p9 / / / / / /
a checkmk checkmk 2.4.0 / / / / / / /
a checkmk checkmk 2.4.0 - / / / / / /
a checkmk checkmk 2.4.0 b1 / / / / / /
a checkmk checkmk 2.4.0 b2 / / / / / /
a checkmk checkmk 2.4.0 b3 / / / / / /
a checkmk checkmk 2.4.0 b4 / / / / / /
a checkmk checkmk 2.4.0 b5 / / / / / /
a checkmk checkmk 2.4.0 b6 / / / / / /
a checkmk checkmk 2.4.0 p1 / / / / / /
a checkmk checkmk 2.4.0 p10 / / / / / /
a checkmk checkmk 2.4.0 p11 / / / / / /
a checkmk checkmk 2.4.0 p12 / / / / / /
a checkmk checkmk 2.4.0 p13 / / / / / /
a checkmk checkmk 2.4.0 p14 / / / / / /
a checkmk checkmk 2.4.0 p15 / / / / / /
a checkmk checkmk 2.4.0 p16 / / / / / /
a checkmk checkmk 2.4.0 p17 / / / / / /
a checkmk checkmk 2.4.0 p18 / / / / / /
a checkmk checkmk 2.4.0 p19 / / / / / /
a checkmk checkmk 2.4.0 p2 / / / / / /
a checkmk checkmk 2.4.0 p20 / / / / / /
a checkmk checkmk 2.4.0 p21 / / / / / /
a checkmk checkmk 2.4.0 p22 / / / / / /
a checkmk checkmk 2.4.0 p23 / / / / / /
a checkmk checkmk 2.4.0 p24 / / / / / /
a checkmk checkmk 2.4.0 p25 / / / / / /
a checkmk checkmk 2.4.0 p26 / / / / / /
a checkmk checkmk 2.4.0 p27 / / / / / /
a checkmk checkmk 2.4.0 p28 / / / / / /
a checkmk checkmk 2.4.0 p29 / / / / / /
a checkmk checkmk 2.4.0 p3 / / / / / /
a checkmk checkmk 2.4.0 p30 / / / / / /
a checkmk checkmk 2.4.0 p4 / / / / / /
a checkmk checkmk 2.4.0 p5 / / / / / /
a checkmk checkmk 2.4.0 p6 / / / / / /
a checkmk checkmk 2.4.0 p7 / / / / / /
a checkmk checkmk 2.4.0 p8 / / / / / /
a checkmk checkmk 2.4.0 p9 / / / / / /
a checkmk checkmk 2.5.0 - / / / / / /
a checkmk checkmk 2.5.0 b1 / / / / / /
a checkmk checkmk 2.5.0 b2 / / / / / /
a checkmk checkmk 2.5.0 b3 / / / / / /
a checkmk checkmk 2.5.0 p1 / / / / / /
a checkmk checkmk 2.5.0 p2 / / / / / /
a checkmk checkmk 2.5.0 p3 / / / / / /
a checkmk checkmk 2.5.0 p4 / / / / / /

CVSS Score

4.8 / 10

CVSS Data - 4.0

  • Attack Vector: NETWORK
  • Attack Complexity: LOW
  • Attack Requirements: NONE
  • Privileges Required: HIGH
  • User Interaction: PASSIVE
  • Scope:
  • Confidentiality Impact: NONE
  • Integrity Impact: LOW
  • Availability Impact: NONE
  • Exploit Maturity: NOT_DEFINED
  • 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

    View Vector String

Timeline

Published: June 8, 2026, 1:16 p.m.
Last Modified: June 8, 2026, 3:53 p.m.

Status : Analyzed

CVE has been recently published to the CVE List and has been received by the NVD.

More info

*Disclaimer: Some vulnerabilities do not have an associated CPE. To enhance the data, we use AI to infer CPEs based on CVE details. This is an automated process and might not always be accurate.