CVE-2026-10855 (GCVE-0-2026-10855)

Vulnerability from cvelistv5 – Published: 2026-06-04 13:05 – Updated: 2026-06-04 13:52
VLAI
Title
MISP Event template importer authorization bypass
Summary
An authorization flaw existed in the MISP Event Template Importer overwrite workflow. When importing an event template in overwrite mode, the application checked whether a matching template already existed but did not verify that the importing user belonged to the organization that owned the existing template. As a result, an authenticated user with access to the template import functionality could forcibly overwrite an event template owned by another organization. Successful exploitation could allow unauthorized modification of another organization’s event template, potentially altering template structure, attributes, or metadata used for subsequent event creation or sharing workflows. Site administrators are not affected by this restriction, as they are explicitly allowed to overwrite templates across organizations. The issue was fixed by enforcing an ownership check before overwrite: non-site-admin users may only overwrite templates owned by their own organization.
Severity
5.1 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
Assigner
References
Impacted products
Vendor Product Version
misp misp Affected: 0 , ≤ 2.5.38 (semver)
Create a notification for this product.
Credits
Andras Iklody (the Insomniac MISP lead dev) 🕵️‍♂️ Jeroen Pinoy 🐞
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.


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