CVE-2026-8833
Last modified
CVE-2026-8833 is a medium-severity vulnerability rated 5.4/10 on the CVSS scale. 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.. EPSS estimates a 0.14% chance of exploitation in the next 30 days.
Description
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.
Metrics
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Checkmk | Checkmk | 2.2.0 |
| Checkmk | Checkmk | 2.3.0 |
| Checkmk | Checkmk | 2.4.0 |
| Checkmk | Checkmk | 2.5.0 |
References
- https://checkmk.com/werk/20002Vendor Advisory
Timeline
- Published
- Last Modified
- Status
- Analyzed
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How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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