CVSS2
Attack Vector
NETWORK
Attack Complexity
LOW
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
PARTIAL
AV:N/AC:L/Au:N/C:N/I:N/A:P
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
LOW
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
EPSS
Percentile
51.9%
Synapse is a Matrix reference homeserver written in python (pypi package
matrix-synapse). Matrix is an ecosystem for open federated Instant
Messaging and VoIP. In Synapse before version 1.33.2 “Push rules” can
specify conditions under which they will match, including event_match
,
which matches event content against a pattern including wildcards. Certain
patterns can cause very poor performance in the matching engine, leading to
a denial-of-service when processing moderate length events. The issue is
patched in version 1.33.2. A potential workaround might be to prevent users
from making custom push rules, by blocking such requests at a
reverse-proxy.
OS | Version | Architecture | Package | Version | Filename |
---|---|---|---|---|---|
ubuntu | 18.04 | noarch | matrix-synapse | < any | UNKNOWN |
ubuntu | 20.04 | noarch | matrix-synapse | < any | UNKNOWN |
ubuntu | 22.04 | noarch | matrix-synapse | < any | UNKNOWN |
github.com/matrix-org/synapse/commit/03318a766cac9f8b053db2214d9c332a977d226c (v1.33.2)
github.com/matrix-org/synapse/releases/tag/v1.33.2
github.com/matrix-org/synapse/security/advisories/GHSA-x345-32rc-8h85
launchpad.net/bugs/cve/CVE-2021-29471
nvd.nist.gov/vuln/detail/CVE-2021-29471
security-tracker.debian.org/tracker/CVE-2021-29471
www.cve.org/CVERecord?id=CVE-2021-29471
CVSS2
Attack Vector
NETWORK
Attack Complexity
LOW
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
PARTIAL
AV:N/AC:L/Au:N/C:N/I:N/A:P
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
LOW
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
EPSS
Percentile
51.9%