CVE-2021-0286 Junos OS Evolved: Specially crafted packets may cause the AFT manager process to crash and restart

High 7.5 Published Updated

Attackers can crash the AFT manager process via crafted packets, causing a sustained Denial of Service on Juniper network devices.

Exploited in the wild
Not known
Login needed
Not needed
Attackable
Over the internet
Victim action needed
Not needed
Fix
None listed

What is CVE-2021-0286?

CVE-2021-0286 is a high-severity denial of service vulnerability in Juniper Junos Os Evolved, published on 15 Jul 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

A vulnerability in the handling of exceptional conditions in Juniper Networks Junos OS Evolved (EVO) allows an attacker to send specially crafted packets to the device, causing the Advanced Forwarding Toolkit manager (evo-aftmand-bt or evo-aftmand-zx) process to crash and restart, impacting all traffic going through the FPC, resulting in a Denial of Service (DoS). Continued receipt and processing of these packets will create a sustained Denial of Service (DoS) condition. Following messages will be logged prior to the crash: Feb 2 10:14:39 fpc0 evo-aftmand-bt[16263]: [Error] Nexthop: Failed to get fwd nexthop for nexthop:32710470974358 label:1089551617 for session:18 probe:35 Feb 2 10:14:39 fpc0 evo-aftmand-bt[16263]: [Error] Nexthop: Failed to get fwd nexthop for nexthop:19241453497049 label:1089551617 for session:18 probe:37 Feb 2 10:14:39 fpc0 evo-aftmand-bt[16263]: [Error] Nexthop: Failed to get fwd nexthop for nexthop:19241453497049 label:1089551617 for session:18 probe:44 Feb 2 10:14:39 fpc0 evo-aftmand-bt[16263]: [Error] Nexthop: Failed to get fwd nexthop for nexthop:32710470974358 label:1089551617 for session:18 probe:47 Feb 2 10:14:39 fpc0 audit[16263]: ANOM_ABEND auid=4294967295 uid=0 gid=0 ses=4294967295 pid=16263 comm="EvoAftManBt-mai" exe="/usr/sbin/evo-aftmand-bt" sig=11 Feb 2 10:14:39 fpc0 kernel: audit: type=1701 audit(1612260879.272:17): auid=4294967295 uid=0 gid=0 ses=4294967295 pid=16263 comm="EvoAftManBt-mai" exe="/usr/sbin/evo-aftmand-bt" sig=1 This issue affects Juniper Networks Junos OS Evolved: All versions prior to 20.4R2-EVO; 21.1 versions prior to 21.1R2-EVO.

Weakness: CWE-754, CWE-703

Which versions are affected by CVE-2021-0286?

It affects 1 product.

Products include Juniper Junos Os Evolved.

How do I fix CVE-2021-0286?

No fix has been published for CVE-2021-0286 yet. Limit exposure of the affected software until one is available.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2021-0286 being exploited?

There is no known exploitation of CVE-2021-0286 in the wild and no public exploit code.

All Juniper Junos Os Evolved vulnerabilities

Sources

Also known as GHSA-jq9h-7vhv-whc7.

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