Vulnerability · Published Jun 10, 2025 · Assigned by GitHub_M

CVE-2025-48937matrix-sdk-crypto vulnerable to sender of encrypted events being spoofed by homeserver administrator

Medium 4.9

In plain English

A medium-severity authentication bypass by spoofing in matrix-rust-sdk from matrix-org. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 33% of all known vulnerabilities).

Severity (CVSS 3.1)4.9Medium

Exploit odds (30 days)0.4%top 67.3% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

matrix-rust-sdk is an implementation of a Matrix client-server library in Rust. matrix-sdk-crypto since version 0.8.0 and up to 0.11.0 does not correctly validate the sender of an encrypted event. Accordingly, a malicious homeserver operator can modify events served to clients, making those events appear to the recipient as if they were sent by another user. This vulnerability is fixed in 0.11.1 and 0.12.0.

Affected products (as reported)

Vendor	Product	Versions
matrix-org	matrix-rust-sdk	>= 0.8.0, < 0.11.1

Weakness: CWE-290 · Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:N

References

https://github.com/matrix-org/matrix-rust-sdk/security/advisories/GHSA-x958-rvg6-956w x_refsource_CONFIRM
https://github.com/matrix-org/matrix-rust-sdk/commit/13c1d2048286bbabf5e7bc6b015aafee98f04d55 x_refsource_MISC
https://github.com/matrix-org/matrix-rust-sdk/commit/56980745b4f27f7dc72ac296e6aa003e5d92a75b x_refsource_MISC
https://spec.matrix.org/v1.14/client-server-api/#mmegolmv1aes-sha2 x_refsource_MISC