CVE-2026-103858

MISP contains an incomplete authorization check in the discussion posting functionality. When a user submits a post to a thread or replies to an existing post, the application only verified whether the target thread was restricted to a single organization (org-only distribution). It did not enforce the full thread access control list, including sharing-group membership and event-level visibility. As a result, an authenticated user who is outside the relevant sharing group or who does not have visibility on the associated event could: - Read the thread title and the content of the quoted post - Submit a new post into the discussion thread This constitutes both an information disclosure (reading restricted thread and post content) and an integrity issue (injecting content into a thread the user is not authorized to participate in). Affected: <2.5.48

CVSS

No CVSS.

References

Link	Resource
https://github.com/MISP/MISP/commit/79fbd4c75

Configurations

No configuration.

History

01 Oct 2026, 12:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-01 12:17

Updated : 2026-10-01 15:17

NVD link : CVE-2026-103858

Mitre link : CVE-2026-103858

CVE.ORG link : CVE-2026-103858

JSON object : View

Products Affected

No product.

CWE

CWE-285

Improper Authorization

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