CVE-2021-21394
Synapse Unvalidated Parameter Request Denial of Service Vulnerability
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.
INFO
Published Date :
April 12, 2021, 9:15 p.m.
Last Modified :
Nov. 7, 2023, 3:30 a.m.
Source :
[email protected]
Remotely Exploitable :
Yes !
Impact Score :
3.6
Exploitability Score :
2.8
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2021-21394
.
URL | Resource |
---|---|
https://github.com/matrix-org/synapse/pull/9321 | Patch 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%40lists.fedoraproject.org/message/TNNAJOZNMVMXM6AS7RFFKB4QLUJ4IFEY/ | |
https://pypi.org/project/matrix-synapse/ | Product Third Party Advisory |
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2021-21394
vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2021-21394
vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by [email protected]
May. 14, 2024
Action Type Old Value New Value -
CVE Modified by [email protected]
Nov. 07, 2023
Action Type Old Value New Value Added Reference GitHub, Inc. https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TNNAJOZNMVMXM6AS7RFFKB4QLUJ4IFEY/ [No types assigned] Removed Reference GitHub, Inc. https://lists.fedoraproject.org/archives/list/[email protected]/message/TNNAJOZNMVMXM6AS7RFFKB4QLUJ4IFEY/ -
Modified Analysis by [email protected]
Nov. 23, 2021
Action Type Old Value New Value Changed Reference Type https://lists.fedoraproject.org/archives/list/[email protected]/message/TNNAJOZNMVMXM6AS7RFFKB4QLUJ4IFEY/ No Types Assigned https://lists.fedoraproject.org/archives/list/[email protected]/message/TNNAJOZNMVMXM6AS7RFFKB4QLUJ4IFEY/ Mailing List, Third Party Advisory Added CWE NIST CWE-20 Added CPE Configuration OR *cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:* -
CVE Modified by [email protected]
Aug. 02, 2021
Action Type Old Value New Value Added Reference https://lists.fedoraproject.org/archives/list/[email protected]/message/TNNAJOZNMVMXM6AS7RFFKB4QLUJ4IFEY/ [No Types Assigned] -
Initial Analysis by [email protected]
Apr. 21, 2021
Action Type Old Value New Value Added CVSS V2 NIST (AV:N/AC:L/Au:S/C:N/I:N/A:P) Added CVSS V3.1 NIST AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Changed Reference Type https://github.com/matrix-org/synapse/pull/9321 No Types Assigned https://github.com/matrix-org/synapse/pull/9321 Patch, Third Party Advisory Changed Reference Type https://github.com/matrix-org/synapse/pull/9393 No Types Assigned https://github.com/matrix-org/synapse/pull/9393 Patch, Third Party Advisory Changed Reference Type https://github.com/matrix-org/synapse/security/advisories/GHSA-w9fg-xffh-p362 No Types Assigned https://github.com/matrix-org/synapse/security/advisories/GHSA-w9fg-xffh-p362 Patch, Third Party Advisory Changed Reference Type https://pypi.org/project/matrix-synapse/ No Types Assigned https://pypi.org/project/matrix-synapse/ Product, Third Party Advisory Added CPE Configuration OR *cpe:2.3:a:matrix:synapse:*:*:*:*:*:*:*:* versions from (excluding) 0.17.0 up to (excluding) 1.28.0
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2021-21394
is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2021-21394
weaknesses.
Exploit Prediction
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.
0.28 }} 0.08%
score
0.68804
percentile