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CVE-2021-21394
Good to know:
Date: April 12, 2021
Synapse is a Matrix reference homeserver written in python (pypi package matrix-synapse). Matrix is an ecosystem for open federated Instant Messaging and VoIP. In Synapse before version 1.28.0 Synapse is missing input validation of some parameters on the endpoints used to confirm third-party identifiers could cause excessive use of disk space and memory leading to resource exhaustion. Note that the groups feature is not part of the Matrix specification and the chosen maximum lengths are arbitrary. Not all clients might abide by them. Refer to referenced GitHub security advisory for additional details including workarounds.
Language: Python
Severity Score
Related Resources (9)
Severity Score
Weakness Type (CWE)
Input Validation
CWE-20Top Fix
CVSS v3.1
| Base Score: |
|
|---|---|
| Attack Vector (AV): | NETWORK |
| Attack Complexity (AC): | LOW |
| Privileges Required (PR): | LOW |
| User Interaction (UI): | NONE |
| Scope (S): | UNCHANGED |
| Confidentiality (C): | NONE |
| Integrity (I): | NONE |
| Availability (A): | HIGH |
CVSS v2
| Base Score: |
|
|---|---|
| Access Vector (AV): | NETWORK |
| Access Complexity (AC): | LOW |
| Authentication (AU): | SINGLE |
| Confidentiality (C): | NONE |
| Integrity (I): | NONE |
| Availability (A): | PARTIAL |
| Additional information: |