CVE-2026-45056

matrix-sdk-crypto is a no-network-IO implementation of a state machine that handles end-to-end encryption for Matrix clients. Starting in version 0.12.0 and prior to version 0.17.0, the matrix-sdk-crypto crate was missing a check for the user ID when decrypting an Olm-encrypted event containing the `sender_device_keys` property. This could be exploited to forge an encrypted to-device event, but only if the attacker colludes with the homeserver operator. This issue is fixed in matrix-sdk-crypto 0.17.0. There are no known workarounds for the issue.

CVSS

No CVSS.

References

Link	Resource
https://github.com/matrix-org/matrix-rust-sdk/pull/6553
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-wfq4-36m3-9g42
https://rustsec.org/advisories/RUSTSEC-2026-0159.html

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-11 22:16

Updated : 2026-09-14 19:17

NVD link : CVE-2026-45056

Mitre link : CVE-2026-45056

CVE.ORG link : CVE-2026-45056

JSON object : View

Products Affected

No product.

CWE

CWE-290

Authentication Bypass by Spoofing

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