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.
CVE-2026-45057
This medium-severity CVE scores 4.9 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.2% (12th percentile of EPSS-scored CVEs). GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).
- Lower severity and no public exploit yet
A fix is available — apply it.
- CVSS v3
- 4.9
- EG Score
- 4.9MEDIUMmedium confidence
- EG Risk
- 22EG Risk 22/100CISA SSVC
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity49% × 45%Exploitation0% × 40%Automatability0% × 15%CISA SSVC: Track at every mission impact level.Action: A fix is available. Apply it within your standard update timelines. - EPSS PROB
- 0.2%
- EPSS %ILE
- 13th
- KEV
- Not listed
CISA SSVCTrack at every mission impact level.
A fix is available. Apply it within your standard update timelines.
Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Mission impact is CISA's Mission & Well-being decision point, and only you can judge it: high means the affected system is essential to your organisation's mission, or its compromise could cause irreversible harm to people. CISA's decision table
Published
June 4, 2026
Last Modified
September 30, 2026
Advisory Details (4)
Auto-updated Sep 11, 2026RUSTSEC-2026-0158: matrix-sdk-ui: Incomplete message edit validation in matrix-sdk-ui › RustSec Advisory Database
https://rustsec.org/advisories/RUSTSEC-2026-0158.htmlmatrix-sdk 0.16.1
Patch available: matrix-org/matrix-rust-sdk matrix-sdk-0.16.1
https://github.com/matrix-org/matrix-rust-sdk/releases/tag/matrix-sdk-0.16.1Better edit validation and don't apply invalid edits in the latest event
Patch available: matrix-org/matrix-rust-sdk matrix-sdk-0.17.0 (PR #6454 merged 2026-04-17)
https://github.com/matrix-org/matrix-rust-sdk/pull/6454Incomplete message edit validation · Advisory · matrix-org/matrix-rust-sdk · GitHub
https://github.com/matrix-org/matrix-rust-sdk/security/advisories/GHSA-h97m-27fx-42rxVendor Advisories for CVE-2026-45057(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Affected Packages
(1 across 1 ecosystem)
crates.io(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| matrix-sdk-ui | — |
| — |
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 7× in last 7d / 25× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-10-10 20:00 UTCEPSS rescore
- 2026-10-09 20:07 UTCEPSS rescore
- 2026-10-08 17:12 UTCEPSS rescore
- 2026-10-07 23:48 UTCEPSS rescore
- 2026-10-06 15:18 UTCEPSS rescore
- 2026-10-05 17:43 UTCEPSS rescore
- 2026-10-04 23:22 UTCEPSS rescore
- 2026-10-03 14:25 UTCEPSS rescore
- 2026-10-01 19:50 UTCEPSS rescore
- 2026-09-30 20:05 UTCEG score recompute
- 2026-09-30 15:03 UTCEPSS rescore
- 2026-09-27 13:48 UTCEPSS rescore
- 2026-09-26 15:58 UTCEPSS rescore
- 2026-09-23 17:53 UTCEPSS rescore
- 2026-09-20 20:15 UTCEPSS rescore
- 2026-09-18 19:28 UTCEPSS rescore
- 2026-09-17 19:31 UTCEPSS rescore
- 2026-09-16 14:08 UTCEPSS rescore
- 2026-09-16 05:15 UTCEPSS rescore
- 2026-09-14 18:09 UTCEG score recompute
- 2026-09-14 16:36 UTCEG score recompute
- 2026-09-14 05:23 UTCEG score recompute
- 2026-09-13 16:47 UTCEPSS rescore
- 2026-09-12 15:01 UTCEPSS rescore
- 2026-09-11 21:24 UTCEG score recompute
Show 7 moreShow fewer
- 2026-07-31 05:26 UTCEG score recompute
- 2026-07-26 22:16 UTCEG score recompute
- 2026-07-23 03:16 UTCEG score recompute
- 2026-06-14 23:18 UTCEPSS rescore
- 2026-06-13 23:00 UTCEPSS rescore
- 2026-06-12 23:12 UTCEPSS rescore
- 2026-06-04 15:10 UTCEG score recompute
Related CVEs(same CWE)
Frequently asked(5)
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