CVE-2020-26890
Published: 24 November 2020
Matrix Synapse before 1.20.0 erroneously permits non-standard NaN, Infinity, and -Infinity JSON values in fields of m.room.member events, allowing remote attackers to execute a denial of service attack against the federation and common Matrix clients. If such a malformed event is accepted into the room's state, the impact is long-lasting and is not fixed by an upgrade to a newer version, requiring the event to be manually redacted instead. Since events are replicated to servers of other room members, the impact is not constrained to the server of the event sender.
Priority
Status
| Package | Release | Status |
|---|---|---|
|
matrix-synapse Launchpad, Ubuntu, Debian |
bionic |
Needs triage
|
| focal |
Needs triage
|
|
| groovy |
Ignored
(end of life)
|
|
| hirsute |
Not vulnerable
(1.23.0-1)
|
|
| impish |
Not vulnerable
(1.23.0-1)
|
|
| jammy |
Not vulnerable
(1.23.0-1)
|
|
| kinetic |
Not vulnerable
(1.23.0-1)
|
|
| lunar |
Not vulnerable
(1.23.0-1)
|
|
| mantic |
Not vulnerable
(1.23.0-1)
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(1.20.0-1)
|
|
| xenial |
Does not exist
|
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 7.5 |
| Attack vector | Network |
| Attack complexity | Low |
| Privileges required | None |
| User interaction | None |
| Scope | Unchanged |
| Confidentiality | None |
| Integrity impact | None |
| Availability impact | High |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |