CVE-2021-20177

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.

• CWE-125

• https://bugzilla.redhat.com/show_bug.cgi?id=1914719Issue Tracking, Patch, Third Party Advisory
• https://bugzilla.redhat.com/show_bug.cgi?id=1914719Issue Tracking, Patch, Third Party Advisory

Published

May 26, 2021

Last Modified

Jun 17, 2026

Status

Modified

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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