What’s Vulnerable › Vulnerabilities

CVE-2026-45057: matrix-sdk-ui: Incomplete edit validation

• Severity: medium (CVSS 4.9 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-09-11 · updated 2026-09-30
• Weakness: CWE-345

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.

Affected products

• matrix-org matrix-sdk-ui: before 0.16.1

References

• https://github.com/matrix-org/matrix-rust-sdk/pull/6454
• https://github.com/matrix-org/matrix-rust-sdk/releases/tag/matrix-sdk-0.16.1
• https://github.com/matrix-org/matrix-rust-sdk/security/advisories/GHSA-h97m-27fx-42rx
• https://rustsec.org/advisories/RUSTSEC-2026-0158.html

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