{"id":"GHSA-wfq4-36m3-9g42","summary":"Matrix Rust SDK: Sender-binding gaps in to-device and room-key attribution","details":"### Impact\n\nThe `matrix-sdk-crypto` crate before 0.16.1 is missing a check for the sender's user ID when decrypting an Olm-encrypted to-device message containing the `sender_device_keys` property.\n\nThis could be exploited to spoof the sender of an encrypted to-device message, but only if the attacker colludes with (or is) the homeserver operator.\n\n### Patches\n\nThis issue is fixed in `matrix-sdk-crypto` 0.16.1.\n\n### Workarounds\n\nThere are no known workarounds for the issue.\n\n### References\n\nThis issue was fixed in https://github.com/matrix-org/matrix-rust-sdk/pull/6553.\n\n### For more information\n\nIf you have any questions or comments about this advisory, please email us at [security at matrix.org](mailto:security@matrix.org).","aliases":["CVE-2026-45056","RUSTSEC-2026-0159"],"modified":"2026-06-04T15:00:08.092172510Z","published":"2026-06-04T14:47:05Z","database_specific":{"severity":"MODERATE","github_reviewed":true,"github_reviewed_at":"2026-06-04T14:47:05Z","nvd_published_at":null,"cwe_ids":["CWE-290"]},"references":[{"type":"WEB","url":"https://github.com/matrix-org/matrix-rust-sdk/security/advisories/GHSA-wfq4-36m3-9g42"},{"type":"WEB","url":"https://github.com/matrix-org/matrix-rust-sdk/pull/6553"},{"type":"PACKAGE","url":"https://github.com/matrix-org/matrix-rust-sdk"},{"type":"WEB","url":"https://github.com/matrix-org/matrix-rust-sdk/releases/tag/matrix-sdk-0.16.1"},{"type":"WEB","url":"https://rustsec.org/advisories/RUSTSEC-2026-0159.html"}],"affected":[{"package":{"name":"matrix-sdk-crypto","ecosystem":"crates.io","purl":"pkg:cargo/matrix-sdk-crypto"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0.12.0"},{"fixed":"0.16.1"}]}],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/06/GHSA-wfq4-36m3-9g42/GHSA-wfq4-36m3-9g42.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N"}]}