#VU87523 NULL pointer dereference in Cisco Systems, Inc products - CVE-2024-20266

Vulnerability identifier: #VU87523

Vulnerability risk: Medium

CVSSv4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Green

CVE-ID: CVE-2024-20266

CWE-ID: CWE-476

Exploitation vector: Remote access

Exploit availability: No public exploit available

Vulnerable software:
Cisco IOS XR
Cisco 8000 Series Routers
Cisco 8201 Router
Cisco 8202 Router
Cisco 8808 Router
Cisco 8812 Router
Cisco 8818 Router
Cisco ASR 9000 Series Aggregation Services Routers
Cisco ASR 9001 Router
Cisco ASR 9006 Router
Cisco ASR 9010 Router
Cisco ASR 9901 Router
Cisco ASR 9902 Router
Cisco ASR 9903 Router
Cisco ASR 9904 Router
Cisco ASR 9906 Router
Cisco ASR 9910 Router
Cisco ASR 9912 Router
Cisco CRS-1 16-Slot Line Card Chassis
Cisco CRS-1 16-Slot Single-Shelf System
Cisco CRS-1 4-Slot Single-Shelf System
Cisco CRS-1 8-Slot Line Card Chassis
Cisco CRS-1 8-Slot Single-Shelf System
Cisco CRS-1 Fabric Card Chassis
Cisco CRS-1 Line Card Chassis (Dual)
Cisco CRS-1 Line Card Chassis (Multi)
Cisco CRS-1 Multishelf System
Cisco CRS-3 4-Slot Single-Shelf System
Cisco CRS-3 8-Slot Single-Shelf System
Cisco CRS-3 Multishelf System
Cisco CRS-X 16-Slot Single-Shelf System
Cisco CRS-X 8-Slot Single-Shelf System
Cisco CRS-X Multishelf System
Cisco IOS XRv 9000 Router
Cisco NCS 4001
Cisco NCS 4009
Cisco NCS 4016
Cisco NCS 540-12Z20G-SYS-A Router
Cisco NCS 540-12Z20G-SYS-D Router
Cisco NCS 540-24Q8L2DD-SYS Router
Cisco NCS 540-24Z8Q2C-SYS Router
Cisco NCS 540-28Z4C-SYS-A Router
Cisco NCS 540-28Z4C-SYS-D Router
Cisco NCS 540-6Z14S-SYS-D Router
Cisco NCS 540-6Z18G-SYS-D Router
Cisco NCS 540-ACC-SYS Router
Cisco NCS 540-FH-AGG Router
Cisco NCS 540-FH-CSR-SYS Router
Cisco NCS 540X-12Z16G-SYS-A Router
Cisco NCS 540X-12Z16G-SYS-D Router
Cisco NCS 540X-16Z4G8Q2C-A Router
Cisco NCS 540X-16Z4G8Q2C-D Router
Cisco NCS 540X-16Z8Q2C-D Router
Cisco NCS 540X-4Z14G2Q-A Router
Cisco NCS 540X-4Z14G2Q-D Router
Cisco NCS 540X-6Z18G-SYS-A Router
Cisco NCS 540X-6Z18G-SYS-D Router
Cisco NCS 540X-8Z16G-SYS-A Router
Cisco NCS 540X-8Z16G-SYS-D Router
Cisco NCS 540X-ACC-SYS Router
Cisco NCS 560-4-SYS Router
Cisco NCS 560-4-SYS-E Router
Cisco NCS 560-4-SYS-E-CC Router
Cisco NCS 560-7-SYS Router
Cisco NCS 560-7-SYS-E Router
Cisco NCS 6008 - 8-Slot Chassis
Cisco Network Convergence System 1001
Cisco Network Convergence System 1002
Cisco Network Convergence System 1004
Cisco Network Convergence System 4000 Series
Cisco Network Convergence System 500 Series Routers
Cisco Network Convergence System 5000 Series
Cisco Network Convergence System 5001
Cisco Network Convergence System 5002
Cisco Network Convergence System 5011
Cisco Network Convergence System 540 Router
Cisco Network Convergence System 540 Series Routers
Cisco Network Convergence System 5500 Series
Cisco Network Convergence System 5501
Cisco Network Convergence System 5501-SE
Cisco Network Convergence System 5502
Cisco Network Convergence System 5502-SE
Cisco Network Convergence System 5504
Cisco Network Convergence System 5508
Cisco Network Convergence System 5516
Cisco Network Convergence System 55A1-24H
Cisco Network Convergence System 55A1-24Q6H-S
Cisco Network Convergence System 55A1-24Q6H-SS
Cisco Network Convergence System 55A1-36H
Cisco Network Convergence System 55A1-36H-SE
Cisco Network Convergence System 55A1-48Q6H
Cisco Network Convergence System 55A2-MOD-HD-S
Cisco Network Convergence System 55A2-MOD-S
Cisco Network Convergence System 55A2-MOD-SE-S
Cisco Network Convergence System 560 Router
Cisco Network Convergence System 560 Series Routers
Cisco Network Convergence System 5700 Series
Cisco Network Convergence System 57B1-5DSE-SYS
Cisco Network Convergence System 57B1-6D24-SYS
Cisco Network Convergence System 57C3-MOD
Cisco Network Convergence System 6000 Series Routers
Cisco Network Convergence System NCS-57C1-48Q6-SYS
Cisco Network Convergence System NCS-57D2-18DD-SYS
Cisco ASR 9922 Router
Cisco Carrier Routing System
Cisco Network Convergence System 1000 Series

Software vendor:
Cisco Systems, Inc

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to a NULL pointer dereference error in the DHCP version 4 (DHCPv4) server feature. A remote attacker can pass specially crafted data to the application and perform a denial of service (DoS) attack.

Install updates from vendor's website.

• https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxr-dhcp-dos-3tgPKRdm