CVE catalog
CVE-2020-26890
UBUNTU-CVE-2020-26890
- Severity
- Unknown
- Published
- Updated
- Source
- [NVD] · [CVE record]
- EPSS
- 3.00% · Oct 25, 2026
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.
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Ubuntu | matrix-synapse | pro | 0.19.2+dfsg-6 | vulnerable |
| Ubuntu | matrix-synapse | pro | 0.24.0+dfsg-1 | vulnerable |
| Ubuntu | matrix-synapse | pro | 0.24.0+dfsg-1ubuntu0.1~esm1 | vulnerable |
| Ubuntu | matrix-synapse | pro | 0.24.0+dfsg-1ubuntu0.1~esm4 | vulnerable |
| Ubuntu | matrix-synapse | pro | 1.3.0-1 | vulnerable |
| Ubuntu | matrix-synapse | pro | 1.4.0-1 | vulnerable |
| Ubuntu | matrix-synapse | pro | 1.5.0-1 | vulnerable |
| Ubuntu | matrix-synapse | pro | 1.5.1-1 | vulnerable |
| Ubuntu | matrix-synapse | pro | 1.6.0-1 | vulnerable |
| Ubuntu | matrix-synapse | pro | 1.6.1-1 | vulnerable |
| Ubuntu | matrix-synapse | pro | 1.7.0-2 | vulnerable |
| Ubuntu | matrix-synapse | pro | 1.7.1-1 | vulnerable |
| Ubuntu | matrix-synapse | pro | 1.7.2-1 | vulnerable |
| Ubuntu | matrix-synapse | pro | 1.7.3-1 | vulnerable |
| Ubuntu | matrix-synapse | pro | 1.8.0-1 | vulnerable |
| Ubuntu | matrix-synapse | pro | 1.9.0-1 | vulnerable |
| Ubuntu | matrix-synapse | pro | 1.9.1-1 | vulnerable |
| Ubuntu | matrix-synapse | pro | 1.10.0-1 | vulnerable |
| Ubuntu | matrix-synapse | pro | 1.10.0-2 | vulnerable |
| Ubuntu | matrix-synapse | pro | 1.11.0-1 | vulnerable |
| Ubuntu | matrix-synapse | pro | 1.11.0-1ubuntu0.1~esm2 | vulnerable |
Fixed-version evidence
OpenFactory catalog packages
No matching packages in this catalog.
Observed: