CVE-2026-8833 (GCVE-0-2026-8833)

Vulnerability from cvelistv5 – Published: 2026-06-08 12:06 – Updated: 2026-06-08 13:02
VLAI
Title
XSS in urls
Summary
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.
Severity
8.5 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:H/VI:H/VA:H/SC:N/SI:L/SA:N
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator (v2.0.3)
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
References
URL Tags
https://checkmk.com/werk/20002 vendor-advisory
Impacted products
Vendor Product Version
Checkmk GmbH Checkmk Affected: 2.5.0 , < 2.5.0p5 (semver)
Affected: 2.4.0 , < 2.4.0p31 (semver)
Affected: 2.3.0 , < 2.3.0p48 (semver)
Affected: 2.2.0 (semver)
Create a notification for this product.
Credits
Arvato Systems Offensive Security
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.