CVE-2020-26257

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`).
Cross-site Scripting
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTNIST
6.5 MEDIUM
NETWORK
LOW
LOW
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
GitHub_MCNA
6.5 MEDIUM
NETWORK
LOW
LOW
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CVEADP
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Base Score
CVSS 3.x
EPSS Score
Percentile: 62%
VendorProductVersion
matrixsynapse
𝑥
< 1.23.1
𝑥
= Vulnerable software versions
Debian logo
Debian Releases
Debian Product
Codename
matrix-synapse
sid
1.116.0-3
fixed
trixie
1.116.0-3
fixed
Ubuntu logo
Ubuntu Releases
Ubuntu Product
Codename
matrix-synapse
noble
not-affected
mantic
not-affected
lunar
not-affected
kinetic
ignored
jammy
needs-triage
impish
ignored
hirsute
ignored
groovy
ignored
focal
needs-triage
bionic
needs-triage
xenial
dne
trusty
dne