Your submission was sent successfully! Close

You have successfully unsubscribed! Close

Thank you for signing up for our newsletter!
In these regular emails you will find the latest updates about Ubuntu and upcoming events where you can meet our team.Close

CVE-2021-21393

Published: 12 April 2021

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.

Priority

Medium

Cvss 3 Severity Score

6.5

Score breakdown

Status

Package Release Status
matrix-synapse
Launchpad, Ubuntu, Debian
bionic Not vulnerable
(code not present)
focal Needed

impish Ignored
(end of life)
jammy Needed

trusty Does not exist

upstream
Released (1.28.0-1)
xenial Does not exist

kinetic Ignored
(end of life, was needed)
groovy Ignored
(end of life)
hirsute Ignored
(end of life)
lunar Not vulnerable
(1.64.0-3)
mantic Not vulnerable
(1.64.0-3)

Severity score breakdown

Parameter Value
Base score 6.5
Attack vector Network
Attack complexity Low
Privileges required Low
User interaction None
Scope Unchanged
Confidentiality None
Integrity impact None
Availability impact High
Vector CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H