MISP: Nested Model Alias Key Bypasses Sanitization to Modify Cross-Tenant Rows (CVE-2026-103237) | HOL Guard CVE

High · CVSS 8.3CVE-2026-103237

MISP: Nested Model Alias Key Bypasses Sanitization to Modify Cross-Tenant Rows

Answer in brief

CVE-2026-103237 records a High severity (CVSS 8.3) vulnerability in MISP: Nested Model Alias Key Bypasses Sanitization to Modify Cross-Tenant Rows. The current sources do not mark it as known exploited. The current feed maps MISP/MISP (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 30, 2026Updated Sep 30, 2026Source checked Sep 30, 2026First seen by HOL Sep 30, 2026Material review Sep 30, 2026

Upstream Advisory

Key facts

Risk: High · CVSS 8.3
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

CVSS is 8.3. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps MISP/MISP (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
MISP/MISPgeneric	>=0 <2.5.48	2.5.48

Recommended response

Check inventory. Check lockfiles and deployed manifests for MISP/MISP.
Review the reported fix. Source-reported solution: The fix introduces a defensive save() override in the base model class that refuses to persist any record where the data array simultaneously contains a nested key matching the model alias and other top-level scalar fields, logging a warning and returning false. Additionally, all code paths that sanitize and save records (free-text import, module result processing, object delta merge, attribute bulk edit, sighting capture, shadow attribute proposal, event report creation) now explicitly unset the nested alias key from the data array before calling save(), ensuring the ORM cannot be redirected to an attacker-chosen row. Controller-level request reshaping was also corrected to avoid creating self-referencing data structures.

Evidence timeline and material changes

Published upstream
Sep 30, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 30, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 30, 2026

Sources and claim methodology

GitHub security advisorygithub.com

Upstream source description

MISP contains an improper input validation vulnerability in its ORM save path. When a user submits data through various endpoints (attribute add/edit, event edit, free-text import, sighting capture, shadow attribute proposal, event report creation, object reference add, user admin edit), the application sanitizes the flat record by stripping the primary key and pinning the event_id or object_id to the caller's context. However, the underlying ORM's set() method gives priority to a nested key whose name matches the model alias and discards the outer scalar fields. An authenticated user with basic write permissions can exploit this by embedding a nested block under the model alias key inside their request. The sanitization logic (id removal, event_id pinning) is applied to the outer record, but the ORM binds to the inner record instead, which carries an attacker-chosen id and event_id. This allows the attacker to overwrite, re-parent, or soft-delete rows belonging to other organizations or events they have no read access to. Impact: - Cross-tenant data integrity compromise (attribute values rewritten, objects re-parented to attacker events, rows soft-deleted) - Affects multiple entity types: Attribute, Object, EventReport, Sighting, AttributeTag, ShadowAttribute - Requires only a low-privilege authenticated account with perm_add Affected versions: <2.5.48

Quoted source text, attributed separately from HOL analysis.