A Use-After-Free vulnerability in the Layer 2 Address Learning Daemon (l2ald) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated, adjacent malicious user to cause l2ald to crash leading to a Denial-of-Service (DoS). In an EVPN-VXLAN scenario, when state updates are received and processed by the affected system, the correct order of some processing steps is not ensured, which can lead to an l2ald crash and restart. Whether the crash occurs depends on system internal timing which is outside the attackers control. This issue affects: Junos OS: * All versions prior to 20.4R3-S8, * 21.2 versions prior to 21.2R3-S6, * 21.3 versions prior to 21.3R3-S5, * 21.4 versions prior to 21.4R3-S4, * 22.1 versions prior to 22.1R3-S3, * 22.2 versions prior to 22.2R3-S1, * 22.3 versions prior to 22.3R3,, * 22.4 versions prior to 22.4R2; Junos OS Evolved: * All versions prior to 20.4R3-S8-EVO, * 21.2-EVO versions prior to 21.2R3-S6-EVO, * 21.3-EVO versions prior to 21.3R3-S5-EVO, * 21.4-EVO versions prior to 21.4R3-S4-EVO, * 22.1-EVO versions prior to 22.1R3-S3-EVO, * 22.2-EVO versions prior to 22.2R3-S1-EVO, * 22.3-EVO versions prior to 22.3R3-EVO, * 22.4-EVO versions prior to 22.4R2-EVO.
Vulmon