Live › vulnerability › CVE-2026-20179
Go to dashboardSeveral Cisco products run a Snort 3 engine that inspects GRE-encapsulated traffic and fails to check errors while parsing it. A remote, unauthenticated attacker who sends a crafted GRE packet can restart the Snort 3 detection engine, interrupting packet inspection (denial of service).
Summary written from the sources below. Check the originals before acting.
First seen by InfraStack 2026-10-23 21:57 UTC. All times on this page are UTC.
Organizations running Cisco products that include the Snort 3 detection engine with GRE inspection enabled are exposed to a restart of the inspection engine. The sources do not list the affected product versions or confirm which deployments inspect GRE traffic by default. Teams that do not run Cisco Snort 3 inspection can skip it.
No product ranges from the sources yet.
Each row is the first time that source carried this signal. The analyst’s rows are its own findings.
Multiple Cisco products are affected by a vulnerability in the Snort 3 Generic Routing Encapsulation (GRE) Detection Engine that could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to restart, resulting in an interruption of packet inspection.
This vulnerability is due to incomplete error checking when Snort 3 parses GRE packets. An attacker could exploit this vulnerability by sending a crafted GRE packet to a targeted device to be parsed by Snort. A successful exploit could allow the attacker to cause the Snort 3 Detection Engine to restart unexpectedly, resulting in a DoS condition.
This page as .md · .json · in your agent: get_signal("CVE-2026-20179")
NVD data is provided by NIST and is public domain · EPSS scores by FIRST, used with attribution. Posts quoted belong to their authors.