Vulnerability · Published Sep 9, 2021 · Assigned by cisco

CVE-2021-34713Cisco IOS XR Software for ASR 9000 Series Routers Denial of Service Vulnerability

High 7.4

In plain English

A high-severity security flaw in Cisco IOS XR Software from Cisco. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 30% of all known vulnerabilities).

Severity (CVSS 3.1)7.4High

Exploit odds (30 days)0.4%top 70.0% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

A vulnerability in the Layer 2 punt code of Cisco IOS XR Software running on Cisco ASR 9000 Series Aggregation Services Routers could allow an unauthenticated, adjacent attacker to cause the affected line card to reboot. This vulnerability is due to incorrect handling of specific Ethernet frames that cause a spin loop that can make the network processors unresponsive. An attacker could exploit this vulnerability by sending specific types of Ethernet frames on the segment where the affected line cards are attached. A successful exploit could allow the attacker to cause the affected line card to reboot.

Affected products (as reported)

Vendor	Product	Versions
Cisco	Cisco IOS XR Software	n/a

Weakness: CWE-399 · Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

References

20210908 Cisco IOS XR Software for ASR 9000 Series Routers Denial of Service Vulnerability vendor-advisory, x_refsource_CISCO