High severity · published Jun 14, 2018
CVE-2018-12423
In Synapse before 0.31.2, unauthorised users can hijack rooms when there is no m.room.power_levels event in force
7.5
CVSS
1.8%
EPSS
No
On KEV
Description
In Synapse before 0.31.2, unauthorised users can hijack rooms when there is no m.room.power_levels event in force.
CVSS vector
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.8% · higher than 79% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SY
Synapse · Matrix
before 0.31.2 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2018-12423
CVE.org
https://www.cve.org/CVERecord?id=CVE-2018-12423
Mailing List
https://bugs.debian.org/901549
Third Party Advisory
https://github.com/matrix-org/matrix-doc/issues/1304
Vendor Advisory
https://matrix.org/blog/2018/06/14/security-update-synapse-0-31-2/
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