Cisco IOS XE 17.18 Update Version Cisco IOS XE 17.18.x

Cisco IOS XE 17.18.x release notes for C8400 Secure Series Routers cover 17.18.1a and 17.18.2. Highlights include Hosted Edge Services, SRv6 and GRE-TP enhancements, security policy management, and multiple resolved and open issues.

• Infrastructure resiliency warnings for insecure configurations and legacy protocols, including weak credential storage, SSHv1, SNMPv1/v2, TLS 1.0/1.1, Telnet, FTP/TFTP, and TACACS+ with pre-shared keys and MD5.
• Security Cloud Control integration for managing NGFW policies, security objects, and security profiles.
• Custom IPS signature sets for deploying personalized Snort3 IPS rules.
• Certificate management automation using EST and SCEP for SD-Routing devices.

• Fixed SD-WAN On-Demand Tunnels not expiring when UMTS is enabled.
• Fixed NAT64 static entry removal when deleting a non-existent entry.
• Fixed devices booting into prev_packages.conf after a power outage.
• Fixed NWPI not capturing self-generated syslog traffic.
• Fixed crashes and stability issues including vDaemon DNS channel initialization, FTMD-related crashes, BFD session issues, and control-plane/session count mismatches.

• Hosted Edge Services for direct monitoring and management of Cisco IOx applications from Cisco Catalyst SD-WAN Manager.
• Platform-based licensing with Essentials and Advantage licenses, including portability within the same platform class.
• Enhanced licensing compliance reporting and direct Enterprise Agreement portal access from Cisco SD-WAN Manager.
• Product Analytics enabled by default for telemetry and resource usage insights.
• Cisco Secure Routers Swim and Onboarding tool for upgrading and onboarding devices to Cisco SD-WAN Manager.
• IPv6 data prefix lists, rule sets, and object groups in security policy via Cisco SD-WAN Manager.
• IPv6 GRE-TP protected link support for SRv6 TI-LFA with IS-IS.
• IPv4 GRE-TP protected link support for SR-MPLS TI-LFA with OSPF and IS-IS.
• MVPN Ingress Replication over SRv6.
• SRv6 Path MTU Discovery.
• MAP-T Border Router enhancements for fragmented ICMP, hairpin traffic, and fragmented UDP handling.

• SIG tunnel keepalive command may be ignored when pushed by vManage.
• Incorrect NAT translation from service-vrf to global for self-generated ICMP Time Exceeded packets.
• C11xx devices may fail to onboard using a generic bootstrap file stored on USB.
• Router crashes can occur with SSL VPN, Policy-Based Routing, and NAT.
• Open issues include TLS 1.2 cipher suite control connections, TLOC extension timing problems, and NAT-related ARP and reboot issues.

• Cisco states that from IOS XE 17.18.2 onward, warning messages will appear for insecure features and protocols; administrators should migrate to the recommended secure alternatives.
• Hosted Edge Services monitoring dashboard is introduced in Cisco Catalyst SD-WAN Manager 20.18.x.
• TACACS+ over TLS 1.3 is recommended as the secure alternative to TACACS+ using pre-shared keys and MD5.
• Release notes reference Cisco Bug Search Tool for detailed issue information.

Product Information

Vendor: Cisco

Product: IOS XE

Version: Cisco IOS XE 17.18.x

Release date: Dec 4, 2025