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MISP Incomplete Thread Authorization Allows Unauthorized Read and Post Access to Discussions

Priority LOW 23CWE-285Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Security bypass
Confidentiality · integrity · availability
Low · Low · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-285.

Summary

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

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00219 12th percentileScored 2026-11-07
Fix Fixed MISP (MISP): 2.5.48

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

VendorProductAffected versionsFixed inStatusSource
MISPMISPbefore 2.5.482.5.48Patch availableCNA
  • MISP VendorMISP Affected before 2.5.48 Fixed in 2.5.48 Patch available CNA

CPE names CNA · 1

CPEVersionsRoleVendor
cpe:2.3:a:misp:misp:*:*:*:*:*:*:*:*——MISP
  • cpe:2.3:a:misp:misp:*:*:*:*:*:*:*:* Versions — — ·MISP

Remediation

  • Fix · CNA MISP (MISP) Fixed in 2.5.48

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    MISP 2.5.48

    6 records Highest priority Priority MEDIUM 1 MEDIUM, 5 LOW

    Other records, highest priority first

    • TI-2026-65744 MISP TOTP Code Replay Allows Duplicate Authentication Within Validity PeriodPriority MEDIUM 48
    • TI-2026-65743 MISP HOTP Token Replay via Stale Session-Cached Counter Allows Second-Factor Authentication BypassPriority LOW 35
    • TI-2026-65745 MISP: Object Distribution ACL Bypass via Event Flattening Exposes Organisation-Only AttributesPriority LOW 31

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-103858
  2. 2026-10-03 Alias added: GHSA-vwhj-wmrx-p88c

References

  • 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