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CVE-2021-0244

Junos OS: A race condition in the storm control profile may allow an attacker to cause a Denial of Service condition

Published
Last modified
published
Not listed in CISA KEV
Fix
Fixed in 14.1X53-D49, 15.1R7-S6, 16.1R7-S7, 18.1R3-S5
None on Exploit-DB, Metasploit or GitHub

Summary

A signal handler race condition exists in the Layer 2 Address Learning Daemon (L2ALD) of Juniper Networks Junos OS due to the absence of a specific protection mechanism to avoid a race condition which may allow an attacker to bypass the storm-control feature on devices. This issue is a corner case and only occurs during specific actions taken by an administrator of a device under certain specifics actions which triggers the event. The event occurs less frequently on devices which are not configured with Virtual Chassis configurations, and more frequently on devices configured in Virtual Chassis configurations. This issue is not specific to any particular Junos OS platform. An Indicator of Compromise (IoC) may be seen by reviewing log files for the following error message seen by executing the following show statement: show log messages | grep storm Result to look for: /kernel: GENCFG: op 58 (Storm Control Blob) failed; err 1 (Unknown) This issue affects: Juniper Networks Junos OS: 14.1X53 versions prior to 14.1X53-D49 on EX Series; 15.1 versions prior to 15.1R7-S6; 15.1X49 versions prior to 15.1X49-D191, 15.1X49-D200 on SRX Series; 16.1 versions prior to 16.1R7-S7; 16.2 versions prior to 16.2R2-S11, 16.2R3; 17.1 versions prior to 17.1R2-S11, 17.1R3; 17.2 versions prior to 17.2R2-S8, 17.2R3-S3; 17.3 versions prior to 17.3R2-S5, 17.3R3-S7; 17.4 versions prior to 17.4R2-S9, 17.4R3; 18.1 versions prior to 18.1R3-S5; 18.2 versions prior to 18.2R2-S6, 18.2R3; 18.3 versions prior to 18.3R1-S7, 18.3R2-S3, 18.3R3; 18.4 versions prior to 18.4R1-S5, 18.4R2; 19.1 versions prior to 19.1R1-S4, 19.1R2.

Timeline

  1. CVE published
  2. Record last updated

Affected versions

  • Juniper Networks Junos OS

    From 14.1X53 · fixed in 14.1X53-D49

  • Juniper Networks Junos OS

    From 15.1 · fixed in 15.1R7-S6; From 16.1 · fixed in 16.1R7-S7; From 18.1 · fixed in 18.1R3-S5

  • Juniper Networks Junos OS

    Version range not reported

References 1

kb.juniper.net