Junos OS: jdhcpd will hang on receiving a specific DHCP packet
An Improper Check for Unusual or Exceptional Conditions vulnerability in Juniper DHCP Daemon (jdhcpd) of Juniper Networks Junos OS allows an adjacent, unauthenticated attacker to cause the jdhcpd to consume all the CPU cycles resulting in a Denial of Service (DoS).
On Junos OS devices with forward-snooped-client configured, if an attacker sends a specific DHCP packet to a non-configured interface, this will cause an infinite loop. The DHCP process will have to be restarted to recover the service.
This issue affects:
Juniper Networks Junos OS
* All versions earlier than 20.4R3-S9;
* 21.2 versions earlier than 21.2R3-S7;
* 21.3 versions earlier than 21.3R3-S5;
* 21.4 versions earlier than 21.4R3-S5;
* 22.1 versions earlier than 22.1R3-S4;
* 22.2 versions earlier than 22.2R3-S3;
* 22.3 versions earlier than 22.3R3-S2;
* 22.4 versions earlier than 22.4R2-S2, 22.4R3;
* 23.2 versions earlier than 23.2R2.
Description: CWE-703: Improper Check or Handling of Exceptional Conditions
Type: N/A
CWE ID: N/A
Description: Denial of Service (DoS)
Metrics
Version
Base score
Base severity
Vector
3.1
6.5
MEDIUM
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Version:3.1
Base score:6.5
Base severity: MEDIUM
Vector:
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Metrics Other Info
Impacts
CAPEC ID
Description
Solutions
The following software releases have been updated to resolve this specific issue: Junos OS 20.4R3-S9, 21.2R3-S7, 21.3R3-S5, 21.4R3-S5, 22.1R3-S4, 22.2R3-S3, 22.3R3-S2, 22.4R2-S2, 22.4R3, 23.2R1-S2, 23.2R2, 23.4R1, and all subsequent releases.
Configurations
To be affected a device must be configured with:
[ forwarding-options dhcp-relay group <group-name> interface ... ]
or
[ system services dhcp-local-server group <group-name> interface ... ]
Workarounds
There are no known workarounds for this issue.
Exploits
Juniper SIRT is not aware of any malicious exploitation of this vulnerability.