Vulnerability Description
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.
Related Weaknesses (CWE)
References
- 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
- https://rustsec.org/advisories/RUSTSEC-2026-0159.html
FAQ
What is CVE-2026-45056?
CVE-2026-45056 is a documented vulnerability. 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-cry...
How severe is CVE-2026-45056?
CVSS scoring is not yet available for CVE-2026-45056. Check NVD for updates.
Is there a patch for CVE-2026-45056?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.