MISP contains an authorization bypass in the related events listing functionality. When a user requests the list of events correlated to a given event, the system retrieved related event metadata directly from the correlation table without re-validating the caller's access rights against each related event.

The correlation table stores a snapshot of the event's distribution level and sharing group at the time the correlation was created, and does not carry the published flag. As a result, events that the caller is not permitted to open—because they are unpublished, or because their distribution or sharing group has changed since the correlation was recorded—were still returned with their metadata (title, date, correlating value counts).

Preconditions:

- An authenticated user with access to at least one event in MISP.

- The existence of correlation entries linking that event to other events the user should not be able to view.

Impact:

- Unauthorized disclosure of event metadata (titles, dates, correlation counts) for events the user has no right to access.

- Potential reconnaissance of threat-intelligence event names and timelines across sharing groups.

Affected: MISP versions prior to the fix commit (2ffa97f05).
Advisories

No advisories yet.

Fixes

Solution

The fix enforces proper per-event authorization on the related events query by applying the user's full access-control conditions (including published status, distribution level, and sharing group membership) to the event lookup, rather than relying solely on the stale distribution snapshot stored in the correlation table. This ensures that only events the caller is currently permitted to read are returned in the related events list.


Workaround

No workaround given by the vendor.

History

Fri, 02 Oct 2026 16:15:00 +0000

Type Values Removed Values Added
Description MISP contains an authorization bypass in the related events listing functionality. When a user requests the list of events correlated to a given event, the system retrieved related event metadata directly from the correlation table without re-validating the caller's access rights against each related event. The correlation table stores a snapshot of the event's distribution level and sharing group at the time the correlation was created, and does not carry the published flag. As a result, events that the caller is not permitted to open—because they are unpublished, or because their distribution or sharing group has changed since the correlation was recorded—were still returned with their metadata (title, date, correlating value counts). Preconditions: - An authenticated user with access to at least one event in MISP. - The existence of correlation entries linking that event to other events the user should not be able to view. Impact: - Unauthorized disclosure of event metadata (titles, dates, correlation counts) for events the user has no right to access. - Potential reconnaissance of threat-intelligence event names and timelines across sharing groups. Affected: MISP versions prior to the fix commit (2ffa97f05).
Title MISP Information Disclosure via Related Events Listing Bypassing Per-Event Authorization
First Time appeared Misp
Misp misp
Weaknesses CWE-285
CWE-862
CPEs cpe:2.3:a:misp:misp:*:*:*:*:*:*:*:*
Vendors & Products Misp
Misp misp
References
Metrics cvssV4_0

{'score': 5.3, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N'}


Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: CIRCL

Published:

Updated: 2026-10-02T16:01:32.781Z

Reserved: 2026-10-02T16:01:26.599Z

Link: CVE-2026-104910

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Deferred

Published: 2026-10-02T16:16:48.813

Modified: 2026-10-02T16:16:48.920

Link: CVE-2026-104910

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-10-02T17:45:17Z

Weaknesses