CVE-2021-41281
Synapse Unrestricted File Download Vulnerability
Description
Synapse is a package for Matrix homeservers written in Python 3/Twisted. Prior to version 1.47.1, Synapse instances with the media repository enabled can be tricked into downloading a file from a remote server into an arbitrary directory. No authentication is required for the affected endpoint. The last 2 directories and file name of the path are chosen randomly by Synapse and cannot be controlled by an attacker, which limits the impact. Homeservers with the media repository disabled are unaffected. Homeservers with a federation whitelist are also unaffected, since Synapse will check the remote hostname, including the trailing `../`s, against the whitelist. Server administrators should upgrade to 1.47.1 or later. Server administrators using a reverse proxy could, at the expense of losing media functionality, may block the certain endpoints as a workaround. Alternatively, non-containerized deployments can be adapted to use the hardened systemd config.
INFO
Published Date :
Nov. 23, 2021, 8:15 p.m.
Last Modified :
Nov. 7, 2023, 3:38 a.m.
Source :
[email protected]
Remotely Exploitable :
Yes !
Impact Score :
3.6
Exploitability Score :
3.9
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-2021-41281.
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-2021-41281 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2021-41281 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.
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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/N3WY56LCEZ4ZECLWV5KMAXF2PSMUB4F2/ [No types assigned] Added Reference GitHub, Inc. https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/EU7QRE55U4IUEDLKT5IYPWL3UXMELFAS/ [No types assigned] Removed Reference GitHub, Inc. https://lists.fedoraproject.org/archives/list/[email protected]/message/N3WY56LCEZ4ZECLWV5KMAXF2PSMUB4F2/ Removed Reference GitHub, Inc. https://lists.fedoraproject.org/archives/list/[email protected]/message/EU7QRE55U4IUEDLKT5IYPWL3UXMELFAS/ -
Modified Analysis by [email protected]
Dec. 14, 2021
Action Type Old Value New Value Changed Reference Type https://lists.fedoraproject.org/archives/list/[email protected]/message/EU7QRE55U4IUEDLKT5IYPWL3UXMELFAS/ No Types Assigned https://lists.fedoraproject.org/archives/list/[email protected]/message/EU7QRE55U4IUEDLKT5IYPWL3UXMELFAS/ Mailing List, Third Party Advisory Changed Reference Type https://lists.fedoraproject.org/archives/list/[email protected]/message/N3WY56LCEZ4ZECLWV5KMAXF2PSMUB4F2/ No Types Assigned https://lists.fedoraproject.org/archives/list/[email protected]/message/N3WY56LCEZ4ZECLWV5KMAXF2PSMUB4F2/ Mailing List, Third Party Advisory Added CWE NIST CWE-22 Added CPE Configuration OR *cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:* *cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:* -
CVE Modified by [email protected]
Dec. 09, 2021
Action Type Old Value New Value Added Reference https://lists.fedoraproject.org/archives/list/[email protected]/message/N3WY56LCEZ4ZECLWV5KMAXF2PSMUB4F2/ [No Types Assigned] Added Reference https://lists.fedoraproject.org/archives/list/[email protected]/message/EU7QRE55U4IUEDLKT5IYPWL3UXMELFAS/ [No Types Assigned] -
Initial Analysis by [email protected]
Nov. 29, 2021
Action Type Old Value New Value Added CVSS V2 NIST (AV:N/AC:M/Au:N/C:N/I:P/A:N) Changed Reference Type https://github.com/matrix-org/synapse/commit/91f2bd090 No Types Assigned https://github.com/matrix-org/synapse/commit/91f2bd090 Patch, Third Party Advisory Changed Reference Type https://github.com/matrix-org/synapse/releases/tag/v1.47.1 No Types Assigned https://github.com/matrix-org/synapse/releases/tag/v1.47.1 Release Notes, Third Party Advisory Changed Reference Type https://github.com/matrix-org/synapse/security/advisories/GHSA-3hfw-x7gx-437c No Types Assigned https://github.com/matrix-org/synapse/security/advisories/GHSA-3hfw-x7gx-437c Mitigation, Third Party Advisory Added CPE Configuration OR *cpe:2.3:a:matrix:synapse:*:*:*:*:*:*:*:* versions up to (excluding) 1.47.1
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2021-41281 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-2021-41281
weaknesses.
Exploit Prediction
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.
0.14 }} 0.02%
score
0.50159
percentile