high
7.4
CWE
362
Advisory Published
Updated

CVE-2021-0244: Junos OS: A race condition in the storm control profile may allow an attacker to cause a Denial of Service condition

First published: Thu Apr 22 2021(Updated: )

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.

Credit: sirt@juniper.net

Affected SoftwareAffected VersionHow to fix
Junos OS Evolved=14.1x53
Junos OS Evolved=14.1x53-d10
Junos OS Evolved=14.1x53-d15
Junos OS Evolved=14.1x53-d16
Junos OS Evolved=14.1x53-d20
Junos OS Evolved=14.1x53-d25
Junos OS Evolved=14.1x53-d26
Junos OS Evolved=14.1x53-d27
Junos OS Evolved=14.1x53-d30
Junos OS Evolved=14.1x53-d34
Junos OS Evolved=14.1x53-d35
Junos OS Evolved=14.1x53-d38
Junos OS Evolved=14.1x53-d40
Junos OS Evolved=14.1x53-d42
Junos OS Evolved=14.1x53-d43
Junos OS Evolved=14.1x53-d44
Junos OS Evolved=14.1x53-d45
Junos OS Evolved=14.1x53-d46
Junos OS Evolved=14.1x53-d47
Junos OS Evolved=14.1x53-d48
Juniper EX2300-24T
Juniper EX2300-C
Juniper EX3400
Juniper EX4300-24T
Juniper EX4400-24X
Juniper EX4600
Juniper EX4650
Juniper EX9200
Juniper EX9250
Junos OS Evolved=15.1
Junos OS Evolved=15.1-a1
Junos OS Evolved=15.1-f
Junos OS Evolved=15.1-f1
Junos OS Evolved=15.1-f2
Junos OS Evolved=15.1-f2-s1
Junos OS Evolved=15.1-f2-s2
Junos OS Evolved=15.1-f2-s3
Junos OS Evolved=15.1-f2-s4
Junos OS Evolved=15.1-f3
Junos OS Evolved=15.1-f4
Junos OS Evolved=15.1-f5
Junos OS Evolved=15.1-f5-s7
Junos OS Evolved=15.1-f6
Junos OS Evolved=15.1-f6-s1
Junos OS Evolved=15.1-f6-s10
Junos OS Evolved=15.1-f6-s12
Junos OS Evolved=15.1-f6-s2
Junos OS Evolved=15.1-f6-s3
Junos OS Evolved=15.1-f6-s4
Junos OS Evolved=15.1-f6-s5
Junos OS Evolved=15.1-f6-s6
Junos OS Evolved=15.1-f6-s7
Junos OS Evolved=15.1-f6-s8
Junos OS Evolved=15.1-f6-s9
Junos OS Evolved=15.1-f7
Junos OS Evolved=15.1-r
Junos OS Evolved=15.1-r1
Junos OS Evolved=15.1-r2
Junos OS Evolved=15.1-r3
Junos OS Evolved=15.1-r4
Junos OS Evolved=15.1-r4-s7
Junos OS Evolved=15.1-r4-s8
Junos OS Evolved=15.1-r4-s9
Junos OS Evolved=15.1-r5
Junos OS Evolved=15.1-r5-s1
Junos OS Evolved=15.1-r5-s3
Junos OS Evolved=15.1-r5-s5
Junos OS Evolved=15.1-r5-s6
Junos OS Evolved=15.1-r6
Junos OS Evolved=15.1-r6-s1
Junos OS Evolved=15.1-r6-s2
Junos OS Evolved=15.1-r6-s3
Junos OS Evolved=15.1-r6-s4
Junos OS Evolved=15.1-r6-s6
Junos OS Evolved=15.1-r7
Junos OS Evolved=15.1-r7-s1
Junos OS Evolved=15.1-r7-s2
Junos OS Evolved=15.1-r7-s3
Junos OS Evolved=15.1-r7-s4
Junos OS Evolved=15.1-r7-s5
Junos OS Evolved=16.1
Junos OS Evolved=16.1-r
Junos OS Evolved=16.1-r1
Junos OS Evolved=16.1-r2
Junos OS Evolved=16.1-r3
Junos OS Evolved=16.1-r3-s10
Junos OS Evolved=16.1-r3-s11
Junos OS Evolved=16.1-r3-s8
Junos OS Evolved=16.1-r4
Junos OS Evolved=16.1-r4-s12
Junos OS Evolved=16.1-r4-s2
Junos OS Evolved=16.1-r4-s3
Junos OS Evolved=16.1-r4-s4
Junos OS Evolved=16.1-r4-s6
Junos OS Evolved=16.1-r4-s8
Junos OS Evolved=16.1-r4-s9
Junos OS Evolved=16.1-r5
Junos OS Evolved=16.1-r5-s4
Junos OS Evolved=16.1-r6
Junos OS Evolved=16.1-r6-s1
Junos OS Evolved=16.1-r6-s3
Junos OS Evolved=16.1-r6-s4
Junos OS Evolved=16.1-r6-s6
Junos OS Evolved=16.1-r7
Junos OS Evolved=16.1-r7-s2
Junos OS Evolved=16.1-r7-s3
Junos OS Evolved=16.1-r7-s4
Junos OS Evolved=16.1-r7-s5
Junos OS Evolved=16.1-r7-s6
Junos OS Evolved=16.2
Junos OS Evolved=16.2-r1
Junos OS Evolved=16.2-r1-s6
Junos OS Evolved=16.2-r2
Junos OS Evolved=16.2-r2-s1
Junos OS Evolved=16.2-r2-s10
Junos OS Evolved=16.2-r2-s2
Junos OS Evolved=16.2-r2-s5
Junos OS Evolved=16.2-r2-s6
Junos OS Evolved=16.2-r2-s7
Junos OS Evolved=16.2-r2-s8
Junos OS Evolved=16.2-r2-s9
Junos OS Evolved=17.1
Junos OS Evolved=17.1-r1
Junos OS Evolved=17.1-r1-s7
Junos OS Evolved=17.1-r2
Junos OS Evolved=17.1-r2-s1
Junos OS Evolved=17.1-r2-s10
Junos OS Evolved=17.1-r2-s2
Junos OS Evolved=17.1-r2-s3
Junos OS Evolved=17.1-r2-s4
Junos OS Evolved=17.1-r2-s5
Junos OS Evolved=17.1-r2-s6
Junos OS Evolved=17.1-r2-s7
Junos OS Evolved=17.1-r2-s8
Junos OS Evolved=17.1-r2-s9
Junos OS Evolved=17.2
Junos OS Evolved=17.2-r1
Junos OS Evolved=17.2-r1-s1
Junos OS Evolved=17.2-r1-s2
Junos OS Evolved=17.2-r1-s3
Junos OS Evolved=17.2-r1-s4
Junos OS Evolved=17.2-r1-s5
Junos OS Evolved=17.2-r1-s6
Junos OS Evolved=17.2-r1-s7
Junos OS Evolved=17.2-r1-s8
Junos OS Evolved=17.2-r2
Junos OS Evolved=17.2-r2-s11
Junos OS Evolved=17.2-r2-s4
Junos OS Evolved=17.2-r2-s6
Junos OS Evolved=17.2-r2-s7
Junos OS Evolved=17.2-r3
Junos OS Evolved=17.2-r3-s1
Junos OS Evolved=17.2-r3-s2
Junos OS Evolved=17.3
Junos OS Evolved=17.3-r1
Junos OS Evolved=17.3-r1-s1
Junos OS Evolved=17.3-r1-s4
Junos OS Evolved=17.3-r2
Junos OS Evolved=17.3-r2-s1
Junos OS Evolved=17.3-r2-s2
Junos OS Evolved=17.3-r2-s3
Junos OS Evolved=17.3-r2-s4
Junos OS Evolved=17.3-r3
Junos OS Evolved=17.3-r3-s1
Junos OS Evolved=17.3-r3-s10
Junos OS Evolved=17.3-r3-s2
Junos OS Evolved=17.3-r3-s3
Junos OS Evolved=17.3-r3-s4
Junos OS Evolved=17.3-r3-s5
Junos OS Evolved=17.3-r3-s6
Junos OS Evolved=17.4
Junos OS Evolved=17.4-r1
Junos OS Evolved=17.4-r1-s1
Junos OS Evolved=17.4-r1-s2
Junos OS Evolved=17.4-r1-s3
Junos OS Evolved=17.4-r1-s4
Junos OS Evolved=17.4-r1-s5
Junos OS Evolved=17.4-r1-s6
Junos OS Evolved=17.4-r1-s7
Junos OS Evolved=17.4-r2
Junos OS Evolved=17.4-r2-s1
Junos OS Evolved=17.4-r2-s2
Junos OS Evolved=17.4-r2-s3
Junos OS Evolved=17.4-r2-s4
Junos OS Evolved=17.4-r2-s5
Junos OS Evolved=17.4-r2-s6
Junos OS Evolved=17.4-r2-s7
Junos OS Evolved=17.4-r2-s8
Junos OS Evolved=18.1
Junos OS Evolved=18.1-r1
Junos OS Evolved=18.1-r2
Junos OS Evolved=18.1-r2-s1
Junos OS Evolved=18.1-r2-s2
Junos OS Evolved=18.1-r2-s4
Junos OS Evolved=18.1-r3
Junos OS Evolved=18.1-r3-s1
Junos OS Evolved=18.1-r3-s2
Junos OS Evolved=18.1-r3-s3
Junos OS Evolved=18.1-r3-s4
Junos OS Evolved=18.2
Junos OS Evolved=18.2-r1
Junos OS Evolved=18.2-r1-s2
Junos OS Evolved=18.2-r1-s3
Junos OS Evolved=18.2-r1-s4
Junos OS Evolved=18.2-r1-s5
Junos OS Evolved=18.2-r2
Junos OS Evolved=18.2-r2-s1
Junos OS Evolved=18.2-r2-s2
Junos OS Evolved=18.2-r2-s3
Junos OS Evolved=18.2-r2-s4
Junos OS Evolved=18.2-r2-s5
Junos OS Evolved=18.3
Junos OS Evolved=18.3-r1
Junos OS Evolved=18.3-r1-s1
Junos OS Evolved=18.3-r1-s2
Junos OS Evolved=18.3-r1-s3
Junos OS Evolved=18.3-r1-s4
Junos OS Evolved=18.3-r1-s5
Junos OS Evolved=18.3-r1-s6
Junos OS Evolved=18.3-r2
Junos OS Evolved=18.3-r2-s1
Junos OS Evolved=18.3-r2-s2
Junos OS Evolved=19.1
Junos OS Evolved=19.1-r1
Junos OS Evolved=19.1-r1-s1
Junos OS Evolved=19.1-r1-s2
Junos OS Evolved=19.1-r1-s3
Junos OS Evolved=15.1x49
Junos OS Evolved=15.1x49-d10
Junos OS Evolved=15.1x49-d100
Junos OS Evolved=15.1x49-d110
Junos OS Evolved=15.1x49-d120
Junos OS Evolved=15.1x49-d130
Junos OS Evolved=15.1x49-d131
Junos OS Evolved=15.1x49-d140
Junos OS Evolved=15.1x49-d15
Junos OS Evolved=15.1x49-d150
Junos OS Evolved=15.1x49-d160
Junos OS Evolved=15.1x49-d170
Junos OS Evolved=15.1x49-d180
Junos OS Evolved=15.1x49-d190
Junos OS Evolved=15.1x49-d20
Junos OS Evolved=15.1x49-d25
Junos OS Evolved=15.1x49-d30
Junos OS Evolved=15.1x49-d35
Junos OS Evolved=15.1x49-d40
Junos OS Evolved=15.1x49-d45
Junos OS Evolved=15.1x49-d50
Junos OS Evolved=15.1x49-d55
Junos OS Evolved=15.1x49-d60
Junos OS Evolved=15.1x49-d65
Junos OS Evolved=15.1x49-d70
Junos OS Evolved=15.1x49-d75
Junos OS Evolved=15.1x49-d80
Junos OS Evolved=15.1x49-d90
Juniper SRX1500
Juniper SRX300
Juniper SRX320
Juniper SRX340
Juniper SRX345
Juniper SRX380
Juniper SRX4100
Juniper SRX4200
Juniper SRX4600
Juniper SRX5400
Juniper SRX550
Juniper SRX5600
Juniper SRX5800

Remedy

The following software releases have been updated to resolve this specific issue: 14.1X53-D49, 15.1R7-S6, 15.1X49-D191, 15.1X49-D200, 15.1X53-D592, 16.1R7-S7, 16.1R8, 16.2R2-S11, 16.2R3, 17.1R2-S11, 17.1R3, 17.2R2-S8, 17.2R3-S3, 17.3R2-S5, 17.3R3-S7, 17.4R2-S9, 17.4R3, 18.1R3-S5, 18.2R2-S6, 18.2R3, 18.3R1-S7, 18.3R2-S3, 18.3R3, 18.4R1-S5, 18.4R2, 19.1R1-S4, 19.1R2, 19.2R1, and all subsequent releases.

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Reference Links

Frequently Asked Questions

  • What is the severity of CVE-2021-0244?

    CVE-2021-0244 has a severity rating classified as high due to its potential for allowing attackers to bypass storm-control features.

  • How do I fix CVE-2021-0244?

    To remediate CVE-2021-0244, it is recommended to upgrade to a fixed version of Junos OS as specified by Juniper Networks.

  • Which versions of Junos OS are affected by CVE-2021-0244?

    CVE-2021-0244 affects multiple versions of Junos OS including 14.1x53, 15.1, 16.1, and other specified iterations.

  • What types of attacks are possible due to CVE-2021-0244?

    An attacker can potentially exploit CVE-2021-0244 to bypass storm-control mechanisms, leading to network disruptions.

  • Is there a patch available for CVE-2021-0244?

    Yes, Juniper Networks has made patches available in subsequent software updates for affected versions regarding CVE-2021-0244.

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