CVE-2020-26257
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CVSS Score
V3.1EPSS Score
v2025.03.14There is a 0.5% chance that this vulnerability will be exploited in the wild within the next 30 days.
Attack Vector Metrics
Impact Metrics
Description
Matrix is an ecosystem for open federated Instant Messaging and VoIP. Synapse is a reference "homeserver" implementation of Matrix. A malicious or poorly-implemented homeserver can inject malformed events into a room by specifying a different room id in the path of a `/send_join`, `/send_leave`, `/invite` or `/exchange_third_party_invite` request. This can lead to a denial of service in which future events will not be correctly sent to other servers over federation. This affects any server which accepts federation requests from untrusted servers. The Matrix Synapse reference implementation before version 1.23.1 the implementation is vulnerable to this injection attack. Issue is fixed in version 1.23.1. As a workaround homeserver administrators could limit access to the federation API to trusted servers (for example via `federation_domain_whitelist`).
Available Exploits
Related News
Affected Products
Affected Versions:
GitHub Security Advisories
Community-driven vulnerability intelligence from GitHub
Denial of service attack via incorrect parameters in Matrix Synapse
GHSA-hxmp-pqch-c8mmAdvisory Details
Affected Packages
CVSS Scoring
CVSS Score
CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
References
Advisory provided by GitHub Security Advisory Database. Published: December 9, 2020, Modified: September 24, 2024