CVE-2021-21273
Synapse Cross-Site Request Forgery and Request Smuggling 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 1.25.0, requests to user provided domains were not restricted to external IP addresses when calculating the key validity for third-party invite events and sending push notifications. This could cause Synapse to make requests to internal infrastructure. The type of request was not controlled by the user, although limited modification of request bodies was possible. For the most thorough protection server administrators should remove the deprecated `federation_ip_range_blacklist` from their settings after upgrading to Synapse v1.25.0 which will result in Synapse using the improved default IP address restrictions. See the new `ip_range_blacklist` and `ip_range_whitelist` settings if more specific control is necessary.
INFO
Published Date :
Feb. 26, 2021, 6:15 p.m.
Last Modified :
Nov. 7, 2023, 3:29 a.m.
Source :
[email protected]
Remotely Exploitable :
Yes !
Impact Score :
2.7
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-2021-21273.
| URL | Resource |
|---|---|
| https://github.com/matrix-org/synapse/commit/30fba6210834a4ecd91badf0c8f3eb278b72e746 | Patch Third Party Advisory |
| https://github.com/matrix-org/synapse/pull/8821 | Patch Third Party Advisory |
| https://github.com/matrix-org/synapse/releases/tag/v1.25.0 | Third Party Advisory |
| https://github.com/matrix-org/synapse/security/advisories/GHSA-v936-j8gp-9q3p | Patch Third Party Advisory |
| https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TNNAJOZNMVMXM6AS7RFFKB4QLUJ4IFEY/ |
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-2021-21273 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2021-21273 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-601 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]
Mar. 05, 2021
Action Type Old Value New Value Added CVSS V2 Metadata Victim must voluntarily interact with attack mechanism Added CVSS V2 NIST (AV:N/AC:M/Au:N/C:P/I:P/A:N) Added CVSS V3.1 NIST AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Changed Reference Type https://github.com/matrix-org/synapse/commit/30fba6210834a4ecd91badf0c8f3eb278b72e746 No Types Assigned https://github.com/matrix-org/synapse/commit/30fba6210834a4ecd91badf0c8f3eb278b72e746 Patch, Third Party Advisory Changed Reference Type https://github.com/matrix-org/synapse/pull/8821 No Types Assigned https://github.com/matrix-org/synapse/pull/8821 Patch, Third Party Advisory Changed Reference Type https://github.com/matrix-org/synapse/releases/tag/v1.25.0 No Types Assigned https://github.com/matrix-org/synapse/releases/tag/v1.25.0 Third Party Advisory Changed Reference Type https://github.com/matrix-org/synapse/security/advisories/GHSA-v936-j8gp-9q3p No Types Assigned https://github.com/matrix-org/synapse/security/advisories/GHSA-v936-j8gp-9q3p Patch, Third Party Advisory Added CPE Configuration OR *cpe:2.3:a:matrix:synapse:*:*:*:*:*:*:*:* versions up to (excluding) 1.25.0
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2021-21273 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-2021-21273
weaknesses.
Exploit Prediction
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.
0.09 }} 0.01%
score
0.38862
percentile