CVE-2025-49090

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

CVSS 3.1

7.1CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:N/I:H/A:L

EPSS

0.5% chance of exploitation in the next 30 days; higher than 40% of CVEs (scores of 2026-10-25)

CWE

CWE-642

Published

2025-10-02

Modified

2026-10-12

Record from

the NVD, synced 2026-10-19

References

• https://github.com/Nheko-Reborn/nheko/issues/1931
• https://github.com/matrix-org/matrix-spec/releases/tag/v1.16
• https://matrix.org/blog/2025/08/project-hydra-improving-state-res/
• https://matrix.org/blog/2025/08/security-release/

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