A high-severity flaw in Cisco’s IOS XR software could allow unauthenticated, remote attackers to cripple Cisco Aggregation Services Routers (ASR).
The flaw stems from Cisco IOS XR, a train of Cisco Systems’ widely deployed Internetworking Operating System (IOS). The OS powers the Cisco ASR 9000 series, which are fully distributed routers engineered to address massive surges in video traffic.
The flaw (CVE-2020-26070), which ranks 8.6 out of 10 on the CVSS scale, stems from an issue with the ingress packet processing function of Cisco IOS XR software. Ingress packet processing is a technique used to sort through incoming packets from different networks.
The vulnerability is due to improper resource allocation when an affected device processes network traffic. An attacker could exploit the flaw by sending specific streams of Layer 2 or Layer 3 protocol data units (PDUs) to an affected device, ultimately exhausting its buffer resources and crashing the device.
When a device is experiencing buffer resources exhaustion, the following message may be seen in the system logs: “%PKT_INFRA-spp-4-PKT_ALLOC_FAIL : Failed to allocate n packets for sending”.
The device would need to be restarted to regain functionality, said Cisco. This vulnerability affects Cisco ASR 9000 series routers if they are running a Cisco IOS XR Software release earlier than releases 6.7.2 or 7.1.2. Cisco fixed this vulnerability in Cisco IOS XR Software releases 6.7.2 and later and releases 7.1.2 and later.
SMU Download (version 6.4.2)= https://mega.nz/file/qV0RDIxS#Lt9OWFC1m8Y4b5fSlKsmpEKtjo8YRgk_oVZnnmv81Gw
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