Medium severity · published Jun 6, 2023
CVE-2023-32682
Synapse is a Matrix protocol homeserver written in Python with the Twisted framework
5.4
CVSS
0.8%
EPSS
No
On KEV
Description
Synapse is a Matrix protocol homeserver written in Python with the Twisted framework. In affected versions it may be possible for a deactivated user to login when using uncommon configurations. This only applies if any of the following are true: 1. JSON Web Tokens are enabled for login via the `jwt_config.enabled` configuration setting. 2. The local password database is enabled via the `password_config.enabled` and `password_config.localdb_enabled` configuration settings *and* a user's password is updated via an admin API after a user is deactivated. Note that the local password database is enabled by default, but it is uncommon to set a user's password after they've been deactivated. Installations that are configured to only allow login via Single Sign-On (SSO) via CAS, SAML or OpenID Connect (OIDC); or via an external password provider (e.g. LDAP) are not affected. If not using JSON Web Tokens, ensure that deactivated users do not have a password set. This issue has been addressed in version 1.85.0. Users are advised to upgrade.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.8% · higher than 55% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SY
Synapse · Matrix
before 1.85.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2023-32682
CVE.org
https://www.cve.org/CVERecord?id=CVE-2023-32682
Patch
https://github.com/matrix-org/synapse/pull/15624
Patch
https://github.com/matrix-org/synapse/pull/15634
Mitigation
https://github.com/matrix-org/synapse/security/advisories/GHSA-26c5-ppr8-f33p
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/X6DH5A5YEB5LRIPP32OUW25FCGZFCZU2/
Product
https://matrix-org.github.io/synapse/latest/admin_api/user_admin_api.html#create-or-modify-account
Product
https://matrix-org.github.io/synapse/latest/jwt.html
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