CVE-2021-21394
CVSS V2 Medium 4
CVSS V3 Medium 6.5
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.
Overview
- CVE ID
- CVE-2021-21394
- Assigner
- security-advisories@github.com
- Vulnerability Status
- Analyzed
- Published Version
- 2021-04-12T21:15:14
- Last Modified Date
- 2021-11-23T22:36:08
Weakness Enumerations
CPE Configuration (Product)
| CPE | Vulnerable | Operator | Version Start | Version End |
|---|---|---|---|---|
| cpe:2.3:a:matrix:synapse:*:*:*:*:*:*:*:* | 1 | OR | 1.28.0 | |
| cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:* | 1 | OR |
CVSS Version 2
- Version
- 2.0
- Vector String
- AV:N/AC:L/Au:S/C:N/I:N/A:P
- Access Vector
- NETWORK
- Access Compatibility
- LOW
- Authentication
- SINGLE
- Confidentiality Impact
- NONE
- Integrity Impact
- NONE
- Availability Impact
- PARTIAL
- Base Score
- 4
- Severity
- MEDIUM
- Exploitability Score
- 8
- Impact Score
- 2.9
CVSS Version 3
- Version
- 3.1
- Vector String
- CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- Attack Vector
- NETWORK
- Attack Compatibility
- LOW
- Privileges Required
- LOW
- User Interaction
- NONE
- Scope
- UNCHANGED
- Confidentiality Impact
- NONE
- Availability Impact
- HIGH
- Base Score
- 6.5
- Base Severity
- MEDIUM
- Exploitability Score
- 2.8
- Impact Score
- 3.6
References
| Reference URL | Reference Tags |
|---|---|
| https://github.com/matrix-org/synapse/pull/9321 | Patch Third Party Advisory |
| https://pypi.org/project/matrix-synapse/ | Product Third Party Advisory |
| https://github.com/matrix-org/synapse/pull/9393 | Patch Third Party Advisory |
| https://github.com/matrix-org/synapse/security/advisories/GHSA-w9fg-xffh-p362 | Patch Third Party Advisory |
| https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/TNNAJOZNMVMXM6AS7RFFKB4QLUJ4IFEY/ | Mailing List Third Party Advisory |
Sources
| Source Name | Source URL |
|---|---|
| NIST | https://nvd.nist.gov/vuln/detail/CVE-2021-21394 |
| MITRE | https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-21394 |
History
| Created | Old Value | New Value | Data Type | Notes |
|---|---|---|---|---|
| 2022-05-10 06:45:04 | Added to TrackCVE | |||
| 2022-12-06 01:37:45 | 2021-04-12T21:15Z | 2021-04-12T21:15:14 | CVE Published Date | updated |
| 2022-12-06 01:37:45 | 2021-11-23T22:36:08 | CVE Modified Date | updated | |
| 2022-12-06 01:37:45 | Analyzed | Vulnerability Status | updated |