Critical severity · published Nov 8, 2019
CVE-2019-18835
Matrix Synapse before 1.5.0 mishandles signature checking on some federation APIs
9.8
CVSS
0.9%
EPSS
No
On KEV
Description
Matrix Synapse before 1.5.0 mishandles signature checking on some federation APIs. Events sent over /send_join, /send_leave, and /invite may not be correctly signed, or may not come from the expected servers.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.9% · higher than 58% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SY
Synapse · Matrix
before 1.5.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2019-18835
CVE.org
https://www.cve.org/CVERecord?id=CVE-2019-18835
Patch
https://github.com/matrix-org/synapse/pull/6262
Release Notes
https://github.com/matrix-org/synapse/releases/tag/v1.5.0
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