CVE-2023-20187 - CVE House
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Status published High CVE-2023-20187

A vulnerability in the Multicast Leaf Recycle Elimination (mLRE) feature...

Vulnerability Description

A vulnerability in the Multicast Leaf Recycle Elimination (mLRE) feature of Cisco IOS XE Software for Cisco ASR 1000 Series Aggregation Services Routers could allow an unauthenticated, remote attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition. This vulnerability is due to incorrect handling of certain IPv6 multicast packets when they are fanned out more than seven times on an affected device. An attacker could exploit this vulnerability by sending a specific IPv6 multicast or IPv6 multicast VPN (MVPNv6) packet through the affected device. A successful exploit could allow the attacker to cause a reload of the affected device, resulting in a DoS condition.

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 XE Software
Vulnerable Versions:
3.7.1S, 3.7.2S, 3.7.3S, 3.7.4S, 3.7.5S, 3.7.6S, 3.7.7S, 3.7.2tS, 3.8.0S, 3.8.1S, 3.8.2S, 3.9.1S, 3.9.0S, 3.9.2S, 3.10.0S, 3.10.1S, 3.10.2S, 3.10.3S, 3.10.4S, 3.10.5S, 3.10.6S, 3.10.7S, 3.10.1xbS, 3.10.8S, 3.10.8aS, 3.10.9S, 3.10.10S, 3.11.1S, 3.11.2S, 3.11.0S, 3.11.3S, 3.11.4S, 3.12.0S, 3.12.1S, 3.12.2S, 3.12.3S, 3.12.4S, 3.13.0S, 3.13.1S, 3.13.2S, 3.13.3S, 3.13.4S, 3.13.5S, 3.13.2aS, 3.13.5aS, 3.13.6S, 3.13.7S, 3.13.6aS, 3.13.8S, 3.13.9S, 3.13.10S, 3.14.0S, 3.14.1S, 3.14.2S, 3.14.3S, 3.14.4S, 3.15.0S, 3.15.1S, 3.15.2S, 3.15.3S, 3.15.4S, 3.16.0S, 3.16.1aS, 3.16.2S, 3.16.3S, 3.16.2bS, 3.16.4aS, 3.16.4bS, 3.16.5S, 3.16.6S, 3.16.7S, 3.16.6bS, 3.16.7aS, 3.16.7bS, 3.16.8S, 3.16.9S, 3.16.10S, 3.17.0S, 3.17.1S, 3.17.2S, 3.17.1aS, 3.17.3S, 3.17.4S, 16.2.1, 16.2.2, 16.3.1, 16.3.2, 16.3.3, 16.3.1a, 16.3.4, 16.3.5, 16.3.6, 16.3.7, 16.3.8, 16.3.9, 16.3.10, 16.3.11, 16.4.1, 16.4.2, 16.4.3, 16.5.1, 16.5.1b, 16.5.2, 16.5.3, 16.6.1, 16.6.2, 16.6.3, 16.6.4, 16.6.5, 16.6.6, 16.6.7, 16.6.8, 16.6.9, 16.6.10, 16.7.1, 16.7.2, 16.7.3, 16.8.1, 16.8.1s, 16.8.2, 16.8.3, 16.9.1, 16.9.2, 16.9.1s, 16.9.3, 16.9.4, 16.9.5, 16.9.6, 16.9.7, 16.9.8, 16.10.1, 16.10.1a, 16.10.1s, 16.10.1e, 16.10.2, 16.10.3, 16.11.1, 16.11.1a, 16.11.2, 16.11.1s, 16.12.1, 16.12.1s, 16.12.1a, 16.12.1c, 16.12.2, 16.12.3, 16.12.8, 16.12.2s, 16.12.4, 16.12.3s, 16.12.5, 16.12.6, 16.12.7, 16.12.10a, 17.1.1, 17.1.1s, 17.1.1t, 17.1.3, 17.2.1, 17.2.1r, 17.2.1v, 17.2.2, 17.2.3, 17.3.1, 17.3.2, 17.3.3, 17.3.1a, 17.3.4, 17.3.5, 17.3.4a, 17.3.6, 17.3.7, 17.4.1, 17.4.2, 17.4.1a, 17.4.1b, 17.5.1, 17.5.1a, 17.5.1b, 17.5.1c, 17.6.1, 17.6.2, 17.6.1a, 17.6.3, 17.6.3a, 17.6.4, 17.6.5, 17.6.5a, 17.7.1, 17.7.1a, 17.7.2, 17.10.1, 17.10.1a, 17.8.1, 17.8.1a, 17.9.1, 17.9.2, 17.9.1a, 17.9.3, 17.9.2a, 17.9.3a, 17.11.1, 17.11.1a

Timeline

Official Publish: September 27th, 2023
Last Modified: August 2nd, 2024
Added to House: July 22nd, 2026

CVSS Vectors

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

Weaknesses (CWE)

CWE-823

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.