CVE-2026-103858

Medium

Description

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

SeverityMedium
CVSS5.3
Exploit probability—
ProductMisp
PublishedOct 1, 2026
First seenOct 1, 2026
Weakness typeCWE-285CWE-285

How to fix

Update
  • misp misp2.5.48 or later

Affected products

ProductAffected versionsFixed in
misp mispv < 2.5.482.5.48

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CVE-2026-103858 · Misp · Dark Radar