CVE-2019-1918

published 2019-08-07

CVE-2019-1918: A vulnerability in the implementation of Intermediate System–to–Intermediate System (IS–IS) routing protocol functionality in Cisco IOS XR Software could allow…

Priority P4 34 high 7.4 CVSS 3.1

AV A AC L PR N UI N S C C N I N A H

A vulnerability in the implementation of Intermediate System–to–Intermediate System (IS–IS) routing protocol functionality in Cisco IOS XR Software could allow an unauthenticated attacker who is in the same IS-IS area to cause a denial of service (DoS) condition. The vulnerability is due to incorrect processing of IS–IS link-state protocol data units (PDUs). An attacker could exploit this vulnerability by sending specific link-state PDUs to an affected system to be processed. A successful exploit could allow the attacker to cause incorrect calculations used in the weighted remote shared risk link groups (SRLG) or in the IGP Flexible Algorithm. It could also cause tracebacks to the logs or potentially cause the receiving device to crash the IS–IS process, resulting in a DoS condition.

Affected

5 ranges

Vendor	Product	Version range	Fixed in
cisco	carrier_routing_system	—	—
cisco	carrier_routing_system	—	—
cisco	cisco_ios_xr_software	>= unspecified < n/a	n/a
cisco	ios_xr	—	—
cisco	ios_xr	>= 6.5.2 < 6.6.3	6.6.3

CVSS provenance

nvd v3.1 7.4 HIGH CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

nvd v3.0 7.4 HIGH CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

nvd v2.0 6.1 MEDIUM AV:A/AC:L/Au:N/C:N/I:N/A:C

vendor_cisco 7.4 HIGH

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