---
id: CVE-2025-49090
title: >-
  The Matrix specification before 1.16 (i.e., with a room version before 12 and
  State Resolution before 2.1) has deficient state resolution.
summary: >-
  The Matrix specification before 1.16 (i.e., with a room version before 12 and
  State Resolution before 2.1) has deficient state resolution.
severity: high
cvss: 7.1
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:N/I:H/A:L'
cwe:
  - CWE-642
published: '2025-10-02'
updated: '2026-10-08'
sourceUpdated: '2026-10-08T23:10:00.213'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2025-49090'
references:
  - url: 'https://github.com/Nheko-Reborn/nheko/issues/1931'
    label: cve@mitre.org
  - url: 'https://github.com/matrix-org/matrix-spec/releases/tag/v1.16'
    label: cve@mitre.org
  - url: 'https://matrix.org/blog/2025/08/project-hydra-improving-state-res/'
    label: cve@mitre.org
  - url: 'https://matrix.org/blog/2025/08/security-release/'
    label: cve@mitre.org
tags:
  - nvd
epss: 0.00462
epssPercentile: 0.38089
ingestedAt: '2026-10-08T23:16:47.357Z'
---

## Overview

The Matrix specification before 1.16 (i.e., with a room version before 12 and State Resolution before 2.1) has deficient state resolution.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.