CVE-2026-45057

matrix-sdk-ui: Incomplete edit validation

Published: Sep 11, 2026Updated: Sep 14, 2026 Sources: CVE List NVDCWE-345

4.9MEDIUM

Description

matrix-sdk-ui provides GUI-centric utilities on top of matrix-rust-sdk. The message edit validation logic in the `matrix-sdk-ui` crate prior to 0.17.0 is missing a check: when replacing an encrypted event, the replacement event itself is not required to be encrypted. This enables a malicious homeserver administrators (or actors with equivalent power) to impersonate or spoof messages as if they were sent by a victim user. `matrix-sdk-ui` 0.17.0 fixes the message edit validation logic to align with the algorithm for replacement events[^1] described in the Matrix specification. No known workarounds are available.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:HPrivileges Required

High

UI:NUser Interaction

None

Scope

S:UScope

Unchanged

Impact

C:NConfidentiality

None

I:HIntegrity

High

A:NAvailability

None

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Weaknesses

CWE-345

Affected Products

matrix-org

oss-project·DEaka matrix-js-sdk, matrix appservice irc, synapse

matrix-sdk-uiMixed

Communications / messaging-chat

Exploitability

No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.

Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique

Collection

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References

https://github.com/matrix-org/matrix-rust-sdk/security/advisories/GHSA-h97m-27fx-42rx

github.com

https://github.com/matrix-org/matrix-rust-sdk/pull/6454

github.com

https://github.com/matrix-org/matrix-rust-sdk/releases/tag/matrix-sdk-0.16.1

github.com

and 1 more references View all →

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