CVE-2026-8833
MEDIUM WAF: High
CVSS 5.4
Published: 2026-06-08
CWE-79
Improper neutralization of HTML-encoded characters in the URL validation function in Checkmk <2.5.0p5, <2.4.0p31, <2.3.0p48, and all 2.2.0 versions allows an authenticated user to bypass URL validation and inject malicious URLs such as javascript: URIs, resulting in cross-site scripting when another user interacts with the crafted link.
WAF Coverage Analysis
Cross-Site Scripting (XSS)
High WAF Coverage
OWASP: A03:2021 Injection
941xxx - XSS / XXE
Affected Software
| Vendor | Product | Version |
|---|---|---|
| checkmk | checkmk | 2.2.0 |
| checkmk | checkmk | 2.2.0 |
| checkmk | checkmk | 2.2.0 |
| checkmk | checkmk | 2.2.0 |
| checkmk | checkmk | 2.2.0 |
| checkmk | checkmk | 2.2.0 |
| checkmk | checkmk | 2.2.0 |
| checkmk | checkmk | 2.2.0 |
| checkmk | checkmk | 2.2.0 |
| checkmk | checkmk | 2.2.0 |
References
- checkmk.com (Vendor Advisory)