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
Juniper JUNOS=14.1x53
Juniper JUNOS=14.1x53-d10
Juniper JUNOS=14.1x53-d15
Juniper JUNOS=14.1x53-d16
Juniper JUNOS=14.1x53-d20
Juniper JUNOS=14.1x53-d25
Juniper JUNOS=14.1x53-d26
Juniper JUNOS=14.1x53-d27
Juniper JUNOS=14.1x53-d30
Juniper JUNOS=14.1x53-d34
Juniper JUNOS=14.1x53-d35
Juniper JUNOS=14.1x53-d38
Juniper JUNOS=14.1x53-d40
Juniper JUNOS=14.1x53-d42
Juniper JUNOS=14.1x53-d43
Juniper JUNOS=14.1x53-d44
Juniper JUNOS=14.1x53-d45
Juniper JUNOS=14.1x53-d46
Juniper JUNOS=14.1x53-d47
Juniper JUNOS=14.1x53-d48
Juniper Ex2300
Juniper Ex2300-c
Juniper Ex3400
Juniper Ex4300
Juniper Ex4400
Juniper EX4600
Juniper Ex4650
Juniper Ex9200
Juniper Ex9250
Juniper JUNOS=15.1
Juniper JUNOS=15.1-a1
Juniper JUNOS=15.1-f
Juniper JUNOS=15.1-f1
Juniper JUNOS=15.1-f2
Juniper JUNOS=15.1-f2-s1
Juniper JUNOS=15.1-f2-s2
Juniper JUNOS=15.1-f2-s3
Juniper JUNOS=15.1-f2-s4
Juniper JUNOS=15.1-f3
Juniper JUNOS=15.1-f4
Juniper JUNOS=15.1-f5
Juniper JUNOS=15.1-f5-s7
Juniper JUNOS=15.1-f6
Juniper JUNOS=15.1-f6-s1
Juniper JUNOS=15.1-f6-s10
Juniper JUNOS=15.1-f6-s12
Juniper JUNOS=15.1-f6-s2
Juniper JUNOS=15.1-f6-s3
Juniper JUNOS=15.1-f6-s4
Juniper JUNOS=15.1-f6-s5
Juniper JUNOS=15.1-f6-s6
Juniper JUNOS=15.1-f6-s7
Juniper JUNOS=15.1-f6-s8
Juniper JUNOS=15.1-f6-s9
Juniper JUNOS=15.1-f7
Juniper JUNOS=15.1-r
Juniper JUNOS=15.1-r1
Juniper JUNOS=15.1-r2
Juniper JUNOS=15.1-r3
Juniper JUNOS=15.1-r4
Juniper JUNOS=15.1-r4-s7
Juniper JUNOS=15.1-r4-s8
Juniper JUNOS=15.1-r4-s9
Juniper JUNOS=15.1-r5
Juniper JUNOS=15.1-r5-s1
Juniper JUNOS=15.1-r5-s3
Juniper JUNOS=15.1-r5-s5
Juniper JUNOS=15.1-r5-s6
Juniper JUNOS=15.1-r6
Juniper JUNOS=15.1-r6-s1
Juniper JUNOS=15.1-r6-s2
Juniper JUNOS=15.1-r6-s3
Juniper JUNOS=15.1-r6-s4
Juniper JUNOS=15.1-r6-s6
Juniper JUNOS=15.1-r7
Juniper JUNOS=15.1-r7-s1
Juniper JUNOS=15.1-r7-s2
Juniper JUNOS=15.1-r7-s3
Juniper JUNOS=15.1-r7-s4
Juniper JUNOS=15.1-r7-s5
Juniper JUNOS=16.1
Juniper JUNOS=16.1-r
Juniper JUNOS=16.1-r1
Juniper JUNOS=16.1-r2
Juniper JUNOS=16.1-r3
Juniper JUNOS=16.1-r3-s10
Juniper JUNOS=16.1-r3-s11
Juniper JUNOS=16.1-r3-s8
Juniper JUNOS=16.1-r4
Juniper JUNOS=16.1-r4-s12
Juniper JUNOS=16.1-r4-s2
Juniper JUNOS=16.1-r4-s3
Juniper JUNOS=16.1-r4-s4
Juniper JUNOS=16.1-r4-s6
Juniper JUNOS=16.1-r4-s8
Juniper JUNOS=16.1-r4-s9
Juniper JUNOS=16.1-r5
Juniper JUNOS=16.1-r5-s4
Juniper JUNOS=16.1-r6
Juniper JUNOS=16.1-r6-s1
Juniper JUNOS=16.1-r6-s3
Juniper JUNOS=16.1-r6-s4
Juniper JUNOS=16.1-r6-s6
Juniper JUNOS=16.1-r7
Juniper JUNOS=16.1-r7-s2
Juniper JUNOS=16.1-r7-s3
Juniper JUNOS=16.1-r7-s4
Juniper JUNOS=16.1-r7-s5
Juniper JUNOS=16.1-r7-s6
Juniper JUNOS=16.2
Juniper JUNOS=16.2-r1
Juniper JUNOS=16.2-r1-s6
Juniper JUNOS=16.2-r2
Juniper JUNOS=16.2-r2-s1
Juniper JUNOS=16.2-r2-s10
Juniper JUNOS=16.2-r2-s2
Juniper JUNOS=16.2-r2-s5
Juniper JUNOS=16.2-r2-s6
Juniper JUNOS=16.2-r2-s7
Juniper JUNOS=16.2-r2-s8
Juniper JUNOS=16.2-r2-s9
Juniper JUNOS=17.1
Juniper JUNOS=17.1-r1
Juniper JUNOS=17.1-r1-s7
Juniper JUNOS=17.1-r2
Juniper JUNOS=17.1-r2-s1
Juniper JUNOS=17.1-r2-s10
Juniper JUNOS=17.1-r2-s2
Juniper JUNOS=17.1-r2-s3
Juniper JUNOS=17.1-r2-s4
Juniper JUNOS=17.1-r2-s5
Juniper JUNOS=17.1-r2-s6
Juniper JUNOS=17.1-r2-s7
Juniper JUNOS=17.1-r2-s8
Juniper JUNOS=17.1-r2-s9
Juniper JUNOS=17.2
Juniper JUNOS=17.2-r1
Juniper JUNOS=17.2-r1-s1
Juniper JUNOS=17.2-r1-s2
Juniper JUNOS=17.2-r1-s3
Juniper JUNOS=17.2-r1-s4
Juniper JUNOS=17.2-r1-s5
Juniper JUNOS=17.2-r1-s6
Juniper JUNOS=17.2-r1-s7
Juniper JUNOS=17.2-r1-s8
Juniper JUNOS=17.2-r2
Juniper JUNOS=17.2-r2-s11
Juniper JUNOS=17.2-r2-s4
Juniper JUNOS=17.2-r2-s6
Juniper JUNOS=17.2-r2-s7
Juniper JUNOS=17.2-r3
Juniper JUNOS=17.2-r3-s1
Juniper JUNOS=17.2-r3-s2
Juniper JUNOS=17.3
Juniper JUNOS=17.3-r1
Juniper JUNOS=17.3-r1-s1
Juniper JUNOS=17.3-r1-s4
Juniper JUNOS=17.3-r2
Juniper JUNOS=17.3-r2-s1
Juniper JUNOS=17.3-r2-s2
Juniper JUNOS=17.3-r2-s3
Juniper JUNOS=17.3-r2-s4
Juniper JUNOS=17.3-r3
Juniper JUNOS=17.3-r3-s1
Juniper JUNOS=17.3-r3-s10
Juniper JUNOS=17.3-r3-s2
Juniper JUNOS=17.3-r3-s3
Juniper JUNOS=17.3-r3-s4
Juniper JUNOS=17.3-r3-s5
Juniper JUNOS=17.3-r3-s6
Juniper JUNOS=17.4
Juniper JUNOS=17.4-r1
Juniper JUNOS=17.4-r1-s1
Juniper JUNOS=17.4-r1-s2
Juniper JUNOS=17.4-r1-s3
Juniper JUNOS=17.4-r1-s4
Juniper JUNOS=17.4-r1-s5
Juniper JUNOS=17.4-r1-s6
Juniper JUNOS=17.4-r1-s7
Juniper JUNOS=17.4-r2
Juniper JUNOS=17.4-r2-s1
Juniper JUNOS=17.4-r2-s2
Juniper JUNOS=17.4-r2-s3
Juniper JUNOS=17.4-r2-s4
Juniper JUNOS=17.4-r2-s5
Juniper JUNOS=17.4-r2-s6
Juniper JUNOS=17.4-r2-s7
Juniper JUNOS=17.4-r2-s8
Juniper JUNOS=18.1
Juniper JUNOS=18.1-r1
Juniper JUNOS=18.1-r2
Juniper JUNOS=18.1-r2-s1
Juniper JUNOS=18.1-r2-s2
Juniper JUNOS=18.1-r2-s4
Juniper JUNOS=18.1-r3
Juniper JUNOS=18.1-r3-s1
Juniper JUNOS=18.1-r3-s2
Juniper JUNOS=18.1-r3-s3
Juniper JUNOS=18.1-r3-s4
Juniper JUNOS=18.2
Juniper JUNOS=18.2-r1
Juniper JUNOS=18.2-r1-s2
Juniper JUNOS=18.2-r1-s3
Juniper JUNOS=18.2-r1-s4
Juniper JUNOS=18.2-r1-s5
Juniper JUNOS=18.2-r2
Juniper JUNOS=18.2-r2-s1
Juniper JUNOS=18.2-r2-s2
Juniper JUNOS=18.2-r2-s3
Juniper JUNOS=18.2-r2-s4
Juniper JUNOS=18.2-r2-s5
Juniper JUNOS=18.3
Juniper JUNOS=18.3-r1
Juniper JUNOS=18.3-r1-s1
Juniper JUNOS=18.3-r1-s2
Juniper JUNOS=18.3-r1-s3
Juniper JUNOS=18.3-r1-s4
Juniper JUNOS=18.3-r1-s5
Juniper JUNOS=18.3-r1-s6
Juniper JUNOS=18.3-r2
Juniper JUNOS=18.3-r2-s1
Juniper JUNOS=18.3-r2-s2
Juniper JUNOS=19.1
Juniper JUNOS=19.1-r1
Juniper JUNOS=19.1-r1-s1
Juniper JUNOS=19.1-r1-s2
Juniper JUNOS=19.1-r1-s3
Juniper JUNOS=15.1x49
Juniper JUNOS=15.1x49-d10
Juniper JUNOS=15.1x49-d100
Juniper JUNOS=15.1x49-d110
Juniper JUNOS=15.1x49-d120
Juniper JUNOS=15.1x49-d130
Juniper JUNOS=15.1x49-d131
Juniper JUNOS=15.1x49-d140
Juniper JUNOS=15.1x49-d15
Juniper JUNOS=15.1x49-d150
Juniper JUNOS=15.1x49-d160
Juniper JUNOS=15.1x49-d170
Juniper JUNOS=15.1x49-d180
Juniper JUNOS=15.1x49-d190
Juniper JUNOS=15.1x49-d20
Juniper JUNOS=15.1x49-d25
Juniper JUNOS=15.1x49-d30
Juniper JUNOS=15.1x49-d35
Juniper JUNOS=15.1x49-d40
Juniper JUNOS=15.1x49-d45
Juniper JUNOS=15.1x49-d50
Juniper JUNOS=15.1x49-d55
Juniper JUNOS=15.1x49-d60
Juniper JUNOS=15.1x49-d65
Juniper JUNOS=15.1x49-d70
Juniper JUNOS=15.1x49-d75
Juniper JUNOS=15.1x49-d80
Juniper JUNOS=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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