{"id":"CVE-2020-27633","details":"In FNET 4.6.3, TCP ISNs are improperly random.","modified":"2026-04-12T00:38:04.614498Z","published":"2023-10-10T17:15:10.607Z","references":[{"type":"ADVISORY","url":"https://www.cisa.gov/news-events/ics-advisories/icsa-21-042-01"},{"type":"ADVISORY","url":"https://www.forescout.com"},{"type":"ADVISORY","url":"https://www.forescout.com/resources/numberjack-weak-isn-generation-in-embedded-tcpip-stacks/"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/butok/fnet","events":[{"introduced":"0"},{"last_affected":"fb3c86df5573af27e119f5c7dfc7aa5bd52475a2"}],"database_specific":{"source":"CPE_FIELD","extracted_events":[{"introduced":"0"},{"last_affected":"4.6.3"}],"cpe":"cpe:2.3:a:butok:fnet:4.6.3:*:*:*:*:*:*:*"}}],"versions":["3.1.1","3.6.0","FNET_3.3.0","v3.0.0","v3.2.0","v3.4.0","v3.5.0","v3.6.1","v3.7.0","v3.8.0","v3.8.1","v3.8.2","v3.9.0","v3.9.1","v3.9.2","v3.9.3","v3.9.3pre","v3.9.3prev","v3.9.3updated","v3.9.4","v4.0.0","v4.0.1","v4.0.2","v4.1.0","v4.1.1","v4.2.0","v4.3.0","v4.4.0","v4.4.1","v4.5.0","v4.5.1","v4.5.2","v4.5.3","v4.6.0","v4.6.1","v4.6.2","v4.6.3"],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2020-27633.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N"}]}