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CVE-2026-45056 (GCVE-0-2026-45056)

Vulnerability from cvelistv5 – Published: 2026-09-11 21:13 – Updated: 2026-09-14 18:17
VLAI
Title
Matrix Rust SDK: Sender-binding gaps in to-device and room-key attribution
Summary
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.
Severity
6.9 (Medium)
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
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-14 16:14 UTC
CWE
  • CWE-290 - Authentication Bypass by Spoofing
Assigner
References
Impacted products
Vendor Product Version CPE status
matrix-org matrix-rust-sdk Affected: >= 0.12.0, < 0.16.1
guessed Create a notification for this product.
Show details on NVD website
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