CVE-2026-45057

matrix-sdk-ui: Incomplete edit validation

Published Sep 11, 2026 CVSS 3.1 · 4.9 Medium EPSS < 1% KEV · Not listed
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-h97m-27fx-42rx matrix-sdk-ui: Incomplete edit validation
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Matrix-org
Matrix-org matrix-sdk-ui
Vendors & Products Matrix-org
Matrix-org matrix-sdk-ui
Type Values Removed Values Added
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.
Title matrix-sdk-ui: Incomplete edit validation
Weaknesses CWE-345
References
Metrics cvssV3_1

{'score': 4.9, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Sep 14, 2026, 4:18 PM
Reserved
May 8, 2026, 6:07 PM
Status
Deferred
Published
Sep 11, 2026, 9:17 PM
Modified
Sep 30, 2026, 7:57 PM