CVE-2021-21394 Vulnerability Details

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CVE-2021-21394 Metadata Quick Info

CVE Published: 12/04/2021 | CVE Updated: 03/08/2024 | CVE Year: 2021
Source: GitHub_M | Vendor: matrix-org | Product: synapse
Status : PUBLISHED

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CVE-2021-21394 Description

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.

Metrics

CVSS Version: 3.1 | Base Score: 5.3 MEDIUM
Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H

l➤ Exploitability Metrics:
    Attack Vector (AV)* NETWORK
    Attack Complexity (AC)* HIGH
    Privileges Required (PR)* LOW
    User Interaction (UI)* NONE
    Scope (S)* UNCHANGED

l➤ Impact Metrics:
    Confidentiality Impact (C)* NONE
    Integrity Impact (I)* NONE
    Availability Impact (A)* HIGH

Weakness Enumeration (CWE)

CWE-ID: CWE-20
CWE Name: CWE-20 Improper Input Validation
Source: matrix-org

Common Attack Pattern Enumeration and Classification (CAPEC)

CAPEC-ID:
CAPEC Description:


Source: NVD (National Vulnerability Database).