CVE-2020-26890

Description

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 rooms 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.

Risk Information

Base Score
7.5
MODERATE
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score
Exploitation Probability
0.955

Associated Vulnerability

VulnerabilityOS Platform
Vulnerabilities CVE-2020-26890 are fixed in Python-matrix-synapse 1.20.0Windows
Vulnerabilities CVE-2020-26890 are fixed in Python-matrix-synapse for linux 1.20.0Linux

Patch Details

No records found

References

https://nvd.nist.gov/vuln/detail/CVE-2023-1234
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-1234