CVE-2021-0216 Information

Description

A vulnerability in Juniper Networks Junos OS running on the ACX5448 and ACX710 platforms may cause BFD sessions to flap when a high rate of transit ARP packets are received. This in turn may impact routing protocols and network stability leading to a Denial of Service (DoS) condition. When a high rate of transit ARP packets are exceptioned to the CPU and BFD flaps the following log messages may be seen: bfdd[15864]: BFDD_STATE_UP_TO_DOWN: BFD Session 192.168.14.3 (IFL 232) state Up -> Down LD/RD(17/19) Up time:11:38:17 Local diag: CtlExpire Remote diag: None Reason: Detect Timer Expiry. bfdd[15864]: BFDD_TRAP_SHOP_STATE_DOWN: local discriminator: 17 new state: down interface: irb.998 peer addr: 192.168.14.3 rpd[15839]: RPD_ISIS_ADJDOWN: IS-IS lost L2 adjacency to peer on irb.998 reason: BFD Session Down bfdd[15864]: BFDD_TRAP_SHOP_STATE_UP: local discriminator: 17 new state: up interface: irb.998 peer addr: 192.168.14.3 This issue only affects the ACX5448 Series and ACX710 Series routers. No other products or platforms are affected by this vulnerability. This issue affects Juniper Networks Junos OS: 18.2 versions prior to 18.2R3-S8 on ACX5448; 18.3 versions prior to 18.3R3-S5 on ACX5448; 18.4 versions prior to 18.4R1-S6 18.4R3-S7 on ACX5448; 19.1 versions prior to 19.1R3-S5 on ACX5448; 19.2 versions prior to 19.2R2 19.2R3 on ACX5448; 19.3 versions prior to 19.3R3 on ACX5448; 19.4 versions prior to 19.4R3 on ACX5448; 20.1 versions prior to 20.1R2 on ACX5448; 20.2 versions prior to 20.2R2 on ACX5448 and ACX710.

CVSS Vector

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Reference

https://kb.juniper.net/JSA11118

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

NONE

Availability Impact

NONE

Base Score

HIGH

Base Severity

6.5