CVE-2022-31152: Denial of service due to incorrect application of event authorization rules
7.5
CVSS Score
3.1
Basic Information
CVE ID
GHSA ID
EPSS Score
0.36388%
CWE
Published
8/31/2022
Updated
9/30/2024
KEV Status
No
Technology
Python
Technical Details
CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Package Name | Ecosystem | Vulnerable Versions | First Patched Version |
---|---|---|---|
matrix-synapse | pip | < 1.62.0rc1 | 1.62.0rc1 |
Vulnerability Intelligence
Miggo AI
Root Cause Analysis
The vulnerability stems from missing checks in the event authorization flow. The patch in commit d4b1c0d adds critical validation for: 1) duplicate auth_events entries (CWE-703), and 2) auth_events not matching expected types (CWE-755). The modified function check_state_independent_auth_rules in synapse/event_auth.py lacked these checks in vulnerable versions, as shown by the added validation logic and corresponding test cases in the diff. This directly matches the described vulnerability where invalid events could be accepted.