Description
matrix-sdk-base is the base component to build a Matrix client library. Versions 0.14.1 and prior are unable to handle responses that include custom m.room.join_rules values due to a serialization bug. This can be exploited to cause a denial-of-service condition, if a user is invited to a room with non-standard join rules, the crate's sync process will stall, preventing further processing for all rooms. This is fixed in version 0.16.0.
Affected products
matrix: matrix-rust-sdk
References4
- github.com/matrix-org/matrix-rust-sdk/security/advisories/GHSA-… PatchVendor Advisory
- github.com/matrix-org/matrix-rust-sdk/commit/4ea0418abefab2aa93… Patch
- github.com/matrix-org/matrix-rust-sdk/pull/5924 Issue TrackingPatch
- rustsec.org/advisories/RUSTSEC-2025-0135.html Third Party Advisory
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - CVSS 4.0
-
1.3
LOW
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 39 · as of 11 November 2026
- CWE
- CWE-755
Could this be exploited in your environment?
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