{"id":"ALPINE-CVE-2023-43796","details":"Synapse is an open-source Matrix homeserver Prior to versions 1.95.1 and 1.96.0rc1, cached device information of remote users can be queried from Synapse. This can be used to enumerate the remote users known to a homeserver. System administrators are encouraged to upgrade to Synapse 1.95.1 or 1.96.0rc1 to receive a patch. As a workaround, the `federation_domain_whitelist` can be used to limit federation traffic with a homeserver.","modified":"2026-11-03T06:32:43.415659086Z","published":"2023-10-31T17:15:23.270Z","upstream":["CVE-2023-43796"],"references":[{"type":"ADVISORY","url":"https://security.alpinelinux.org/vuln/CVE-2023-43796"}],"affected":[{"package":{"name":"synapse","ecosystem":"Alpine:v3.18","purl":"pkg:apk/alpine/synapse?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.95.1-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2023-43796.json"}},{"package":{"name":"synapse","ecosystem":"Alpine:v3.19","purl":"pkg:apk/alpine/synapse?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.95.1-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2023-43796.json"}},{"package":{"name":"synapse","ecosystem":"Alpine:v3.20","purl":"pkg:apk/alpine/synapse?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.95.1-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2023-43796.json"}},{"package":{"name":"synapse","ecosystem":"Alpine:v3.21","purl":"pkg:apk/alpine/synapse?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.95.1-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2023-43796.json"}},{"package":{"name":"synapse","ecosystem":"Alpine:v3.22","purl":"pkg:apk/alpine/synapse?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.95.1-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2023-43796.json"}},{"package":{"name":"synapse","ecosystem":"Alpine:v3.23","purl":"pkg:apk/alpine/synapse?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.95.1-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2023-43796.json"}},{"package":{"name":"synapse","ecosystem":"Alpine:v3.24","purl":"pkg:apk/alpine/synapse?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.95.1-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2023-43796.json"}}],"schema_version":"1.9.2","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N"}]}