{"id":"CVE-2021-20177","details":"A flaw was found in the Linux kernel's implementation of string matching within a packet. A privileged user (with root or CAP_NET_ADMIN) when inserting iptables rules could insert a rule which can panic the system. Kernel before kernel 5.5-rc1 is affected.","modified":"2026-03-13T00:47:35.309512Z","published":"2021-05-26T21:15:08.157Z","related":["SUSE-SU-2021:0347-1","SUSE-SU-2021:0348-1","SUSE-SU-2021:0353-1","SUSE-SU-2021:0354-1","SUSE-SU-2021:0427-1","SUSE-SU-2021:0433-1","SUSE-SU-2021:0532-1","openSUSE-SU-2021:0241-1"],"references":[{"type":"FIX","url":"https://bugzilla.redhat.com/show_bug.cgi?id=1914719"}],"affected":[{"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2021-20177.json","unresolved_ranges":[{"events":[{"introduced":"0"},{"last_affected":"5.4.9"}]}]}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H"}]}