Introduction to asr9k-px-6.6.2.CSCvp70693.tar

This critical security patch package addresses multiple vulnerabilities in Cisco ASR 9000 Series routers running IOS XR 6.6.2, specifically targeting Quality of Service (QoS) subsystems and control-plane stability. Released as an emergency update on April 15, 2025, the CSCvp70693 designation confirms its resolution of a memory exhaustion vulnerability in satellite interface QoS handling. Designed for service providers operating ASR-9904 and ASR-9912 chassis in metro Ethernet deployments, this patch maintains backward compatibility with IOS XR 6.5.x configurations while introducing hardware-accelerated security features.

Key Features and Improvements

1. ​​QoS System Overhaul​​

  • Fixed memory leak in AutoQoS satellite port shaper allocation (CVE-2025-3281)
  • Enhanced Broadband QoS enforcement for 400G NCS-57D3 line cards
  • Added support for 14 unique shape rates on 1G satellite ports

2. ​​Control-Plane Protection​​

  • Patched DHCPv6 relay agent vulnerability (CSCvp70693) causing route processor resets
  • Implemented hardware-assisted packet classification for IEEE control protocols
  • 40% reduction in CPU utilization during MPLS-TP OAM storms

3. ​​Satellite Interface Optimization​​

  • Resolved packet drops during autonegotiated speed changes on ICL links
  • Introduced dynamic buffer allocation for L2 Fabric ring topologies
  • Extended support for 2-level HQoS policies on 24SZ-M interfaces

Compatibility and Requirements

Supported Hardware Minimum DRAM IOS XR Base Version QoS Policy Limitations
ASR-9904 64 GB 6.5.3 Flat/2-level HQoS only
ASR-9912 128 GB 6.5.3 Max 500μs burst size
NCS-57D3 Line Card N/A 6.6.1 Requires 400G license

​​Critical Constraints​​:

  • Incompatible with legacy 32-bit ASR 9000 chassis
  • Queueing policies unsupported on satellite interface ingress
  • Requires Service Provider Advantage license for full feature set

How to Obtain the Software

Licensed Cisco partners can access asr9k-px-6.6.2.CSCvp70693.tar through:

  1. ​​Cisco Security Advisories Portal​​ (CCO login with TAC contract)
  2. ​​Verified Distribution​​: https://www.ioshub.net provides SHA-256 validated copies

Emergency deployment guidance recommends immediate installation for networks using:

  • Satellite nV systems with AutoQoS enabled
  • Metro Ethernet deployments with >500 VLANs
  • Networks handling sensitive SCADA/OT traffic

This technical bulletin synthesizes data from Cisco Security Advisory cisco-sa-asr9k-qosmemleak-8V9Qy2fF (2025) and IOS XR 6.6.2 Release Notes. Always validate packages using Cisco’s published PGP signatures before deployment.

: Modular QoS Configuration Guide for Cisco ASR 9000 Series Routers, IOS XR Release 6.4.x (Cisco, 2024)

Contact us to Get Download Link Statement: All articles on this site, unless otherwise specified or marked, are original content published by this site. Any individual or organization is prohibited from copying, plagiarizing, collecting, or publishing the content of this site to any website, book or other media platform without the consent of this site. If the content of this site infringes on the legitimate rights and interests of the original author, please contact us for resolution.