An Improper Check for Unusual or Exceptional Conditions vulnerability in the Layer 2 Address Learning Daemon (l2ald) on Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated, adjacent attacker to cause Denial of Service (DoS).

In an EVPN/VXLAN scenario, when a high amount specific Layer 2 packets are processed by the device, it can cause the Routing Protocol Daemon (rpd) to utilize all CPU resources which causes the device to hang. A manual restart of the rpd is required to restore services.

This issue affects both IPv4 and IPv6 implementations.
This issue affects
Junos OS:
All versions earlier than 21.4R3-S7;
22.1 versions earlier than 22.1R3-S5;
22.2 versions earlier than 22.2R3-S3;
22.3 versions earlier than 22.3R3-S3;
22.4 versions earlier than 22.4R3-S2;
23.2 versions earlier than 23.2R2;
23.4 versions earlier than 23.4R1-S1.

Junos OS Evolved:
All versions earlier than 21.4R3-S7-EVO;
22.1-EVO versions earlier than 22.1R3-S5-EVO;
22.2-EVO versions earlier than 22.2R3-S3-EVO;
22.3-EVO versions earlier than 22.3R3-S3-EVO;
22.4-EVO versions earlier than 22.4R3-S2-EVO;
23.2-EVO versions earlier than 23.2R2-EVO;
23.4-EVO versions earlier than 23.4R1-S1-EVO, 23.4R2-EVO.

Juniper Networks, Inc. CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Juniper Networks, Inc. AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Juniper Networks, Inc. CWE-754

Juniper Networks, Inc. https://supportportal.juniper.net/JSA79175 [No types assigned]