A vulnerability in the DHCP version 4 (DHCPv4) server feature of Cisco IOS XR Software could allow an unauthenticated, remote attacker to trigger a crash of the dhcpd process, resulting in a denial of service (DoS) condition. This vulnerability exists because certain DHCPv4 messages are improperly validated when they are processed by an affected device. An attacker could exploit this vulnerability by sending a malformed DHCPv4 message to an affected device. A successful exploit could allow the attacker to cause a NULL pointer dereference, resulting in a crash of the dhcpd process. While the dhcpd process is restarting, which may take up to approximately two minutes, DHCPv4 server services are unavailable on the affected device. This could temporarily prevent network access to clients that join the network during that time period. Note: Only the dhcpd process crashes and eventually restarts automatically. The router does not reload.
References
| Link | Resource |
|---|---|
| https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxr-dhcp-dos-pjPVReLU | Vendor Advisory |
Configurations
Configuration 1 (hide)
| AND |
|
Configuration 2 (hide)
| AND |
|
Configuration 3 (hide)
| AND |
|
Configuration 4 (hide)
| AND |
|
Configuration 5 (hide)
| AND |
|
Configuration 6 (hide)
| AND |
|
History
22 Sep 2021, 15:10
| Type | Values Removed | Values Added |
|---|---|---|
| CWE | CWE-476 | |
| CVSS |
v2 : v3 : |
v2 : 5.0
v3 : 7.5 |
| References | (CISCO) https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxr-dhcp-dos-pjPVReLU - Vendor Advisory | |
| CPE | cpe:2.3:h:cisco:asr_9912:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:ncs540-24z8q2c-m:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:asr_9006:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:ios_xrv_9000:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:ncs540-28z4c-sys-d:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:ncs_560-7:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:asr_9010:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:asr_9904:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:ncs540-12z20g-sys-a:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:ncs_5502-se:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:asr_9922:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:ncs_5011:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:ncs_5001:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:ncs540-12z20g-sys-d:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:ncs540-28z4c-sys-a:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:asr_9903:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:asr_9001:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:ncs540x-12z16g-sys-d:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:ncs540x-12z16g-sys-a:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:ncs_5002:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:ncs540-acc-sys:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:ncs540x-16z4g8q2c-a:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:ncs540x-acc-sys:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:ncs_5502:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:ncs_5516:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:ncs_5501-se:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:ncs_5501:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:asr_9000v-v2:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:ncs_560-4:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:asr_9901:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:ncs540-24z8q2c-sys:-:*:*:*:*:*:*:* cpe:2.3:o:cisco:ios_xr:*:*:*:*:*:*:*:* cpe:2.3:h:cisco:asr_9902:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:asr_9910:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:asr_9906:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:ncs_5508:-:*:*:*:*:*:*:* cpe:2.3:h:cisco:ncs540x-16z4g8q2c-d:-:*:*:*:*:*:*:* |
09 Sep 2021, 06:15
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2021-09-09 05:15
Updated : 2023-12-10 14:09
NVD link : CVE-2021-34737
Mitre link : CVE-2021-34737
CVE.ORG link : CVE-2021-34737
JSON object : View
Products Affected
cisco
- ncs_5001
- ncs_5508
- ncs_5502-se
- ncs_560-7
- ncs540x-16z4g8q2c-d
- ncs540-28z4c-sys-d
- ios_xrv_9000
- ncs540-12z20g-sys-d
- ncs_560-4
- ncs_5011
- ncs540-12z20g-sys-a
- ncs540x-16z4g8q2c-a
- ncs540x-12z16g-sys-a
- asr_9000v-v2
- ncs540-acc-sys
- ncs540x-acc-sys
- asr_9901
- asr_9006
- asr_9912
- ncs540x-12z16g-sys-d
- ncs540-24z8q2c-sys
- asr_9001
- ncs_5501
- ncs540-28z4c-sys-a
- asr_9906
- ncs540-24z8q2c-m
- asr_9904
- ios_xr
- ncs_5502
- asr_9902
- ncs_5516
- asr_9922
- asr_9903
- ncs_5002
- asr_9010
- asr_9910
- ncs_5501-se
CWE
CWE-476
NULL Pointer Dereference