Skip to main content

Improper Check for Unusual or Exceptional Conditions

CVE-2021-0286

Severity High
Score 7.5/10

Summary

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.

  • LOW
  • NETWORK
  • NONE
  • UNCHANGED
  • NONE
  • NONE
  • NONE
  • HIGH

CWE-754 - Improper Check for Unusual or Exceptional Conditions

The software does not check or incorrectly checks for unusual or exceptional conditions that are not expected to occur frequently during day to day operation of the software.

References

Advisory Timeline

  • Published