CVE-2026-86283
MISP UiBeta Collection View Bypasses Event ACL, Exposing Unauthorized Event Data
Description
MISP's UiBeta theme collection view (app/View/Themed/UiBeta/Collections/view.ctp) performed a secondary query of member events by UUID without applying the caller's access control list (ACL). The CollectionsController::view() action correctly resolved collection element UUIDs through Event::fetchSimpleEvents($user, ...), which enforces per-user event ACL. However, the view template independently re-queried the same UUIDs using only an Event.uuid IN (...) condition, omitting the createEventConditions() authorization filter. Because collection element UUIDs are stored without server-side authorization against the referenced event (CollectionElementsController::add() accepts whatever UUID the collection owner posts), an authenticated user with view access to a collection could retrieve full details of events they are not permitted to read. The exposed data included event identifiers, info, dates, timestamps, creator organization, all event tags, and galaxy clusters (the latter attached via a cluster-scoped rather than event-scoped ACL check). This constitutes an authorization bypass at the presentation layer, allowing horizontal privilege escalation across event boundaries within the MISP instance.
INFO
Published Date :
Sept. 6, 2026, 3:17 p.m.
Last Modified :
Sept. 6, 2026, 3:17 p.m.
Remotely Exploit :
Yes !
Source :
5a6e4751-2f3f-4070-9419-94fb35b644e8
Affected Products
The following products are affected by CVE-2026-86283
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 4.0 | HIGH | 5a6e4751-2f3f-4070-9419-94fb35b644e8 | ||||
| CVSS 4.0 | HIGH | 5a6e4751-2f3f-4070-9419-94fb35b644e8 |
Solution
- Ensure all event queries enforce per-user ACLs.
- Modify the UiBeta theme's view.ctp template.
- Re-query event UUIDs using authorization filters.
- Validate collection element UUIDs against event ACLs.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-86283.
| URL | Resource |
|---|---|
| https://github.com/MISP/MISP/commit/44573e4a8.patch |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-86283 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-86283
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-86283 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-86283 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by 5a6e4751-2f3f-4070-9419-94fb35b644e8
Sep. 06, 2026
Action Type Old Value New Value Added Description MISP's UiBeta theme collection view (app/View/Themed/UiBeta/Collections/view.ctp) performed a secondary query of member events by UUID without applying the caller's access control list (ACL). The CollectionsController::view() action correctly resolved collection element UUIDs through Event::fetchSimpleEvents($user, ...), which enforces per-user event ACL. However, the view template independently re-queried the same UUIDs using only an Event.uuid IN (...) condition, omitting the createEventConditions() authorization filter. Because collection element UUIDs are stored without server-side authorization against the referenced event (CollectionElementsController::add() accepts whatever UUID the collection owner posts), an authenticated user with view access to a collection could retrieve full details of events they are not permitted to read. The exposed data included event identifiers, info, dates, timestamps, creator organization, all event tags, and galaxy clusters (the latter attached via a cluster-scoped rather than event-scoped ACL check). This constitutes an authorization bypass at the presentation layer, allowing horizontal privilege escalation across event boundaries within the MISP instance. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CWE CWE-285 Added CWE CWE-862 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/86xxx/CVE-2026-86283.json">CVE-2026-86283</a> Added Reference https://github.com/MISP/MISP/commit/44573e4a8.patch