CVE-2021-34713 - CVE House
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Status published High CVE-2021-34713

Cisco IOS XR Software for ASR 9000 Series Routers Denial of Service Vulnerability

Vulnerability 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.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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Affected Vendor

Affected Software

Cisco IOS XR Software
Vulnerable Versions:
Unknown

Timeline

Official Publish: September 9th, 2021
Last Modified: November 7th, 2024
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

Weaknesses (CWE)

CWE-399

MITRE ATT&CK TTPs

T1499.001 OS Exhaustion Flood
Impact
T1499.002 Service Exhaustion Flood
Impact
T1499.003 Application Exhaustion Flood
Impact
T1499.004 Application or System Exploitation
Impact