TI-2026-09319 Aliases CVE-2026-10855 GHSA-243v-5f97-vfq3

MISP Event template importer authorization bypass

LOW 22CWE-862Published 2026-06-04 · Updated 2026-06-04

Key facts

Attack vector: Network
Privileges required: High
User interaction: None
Attack complexity: Low
Attack requirements: None
Impact type: Security bypass
Confidentiality · integrity · availability: None · Low · None
Fix status: No fix listed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-862.

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00154 4th percentileScored 2026-11-07

Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: No
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
MISP	misp	up to 2.5.38	—	No fix listed	CNA

misp VendorMISP Affected up to 2.5.38 Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:misp-project:misp::::::::	before 2.5.39	Vulnerable	Misp-project

cpe:2.3:a:misp-project:misp:*:*:*:*:*:*:*:* Versions before 2.5.39 Vulnerable ·Misp-project

Remediation

No fixed version listed by the sources yet.

Timeline

2026-10-02 Threatist record created from CVE-2026-10855
2026-10-03 Alias added: GHSA-243v-5f97-vfq3

References

Patch 1

https://github.com/MISP/MISP/commit/7c2200d143bef86aaf58d701b6968a843097db69

TI-2025-41517 In MISP before 2.5.28, app/View/Elements/Workflows/executionPath.ctp allows XSS in the workflow execution path. CVSS 3.1CRITICAL 9.0
TI-2026-65744 MISP TOTP Code Replay Allows Duplicate Authentication Within Validity Period CVSS 4.0CRITICAL 9.3
TI-2026-54145 Path Traversal in MISP Object Template Resolution During STIX Import and Export in misp-stix library CVSS 4.0HIGH 8.8
TI-2020-10250 MISP MISP-maltego 1.4.4 incorrectly shares a MISP connection across users in a remote-transform use case. CVSS 3.1CRITICAL 9.8
TI-2026-59159 MISP Unauthenticated Mail Endpoints Allow Unbounded Storage Consumption and Request Flooding CVSS 4.0HIGH 8.7
TI-2026-58541 MISP LDAP and LinOTP Authentication Bypass via Empty or Invalid Credentials CVSS 4.0CRITICAL 9.5

See all 182 →

Sources

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