CVE-2025-66622 (GCVE-0-2025-66622)
Vulnerability from cvelistv5 – Published: 2025-12-09 02:07 – Updated: 2025-12-09 16:02
VLAI
EPSS
VEX
Title
matrix-sdk-base is vulnerable to DoS via custom m.room.join_rules event values
Summary
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.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-12-09 14:16 UTC
CWE
- CWE-755 - Improper Handling of Exceptional Conditions
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://github.com/matrix-org/matrix-rust-sdk/sec… | x_refsource_CONFIRM |
| https://github.com/matrix-org/matrix-rust-sdk/pull/5924 | x_refsource_MISC |
| https://github.com/matrix-org/matrix-rust-sdk/com… | x_refsource_MISC |
| https://rustsec.org/advisories/RUSTSEC-2025-0135.html | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| matrix-org | matrix-rust-sdk |
Affected:
< 0.16.0
|
guessed |
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