critical
10
CWE
754
Advisory Published
Updated

CVE-2021-0211: Junos OS and Junos OS Evolved: Upon receipt of a specific BGP FlowSpec message network traffic may be disrupted.

First published: Fri Jan 15 2021(Updated: )

An improper check for unusual or exceptional conditions in Juniper Networks Junos OS and Junos OS Evolved Routing Protocol Daemon (RPD) service allows an attacker to send a valid BGP FlowSpec message thereby causing an unexpected change in the route advertisements within the BGP FlowSpec domain leading to disruptions in network traffic causing a Denial of Service (DoS) condition. Continued receipt of these update messages will cause a sustained Denial of Service condition. This issue affects Juniper Networks: Junos OS: All versions prior to 17.3R3-S10 with the exceptions of 15.1X49-D240 on SRX Series and 15.1R7-S8 on EX Series; 17.3 versions prior to 17.3R3-S10; 17.4 versions prior to 17.4R2-S12, 17.4R3-S4; 18.1 versions prior to 18.1R3-S12; 18.2 versions prior to 18.2R2-S8, 18.2R3-S6; 18.3 versions prior to 18.3R3-S4; 18.4 versions prior to 18.4R1-S8, 18.4R2-S6, 18.4R3-S6; 19.1 versions prior to 19.1R1-S6, 19.1R2-S2, 19.1R3-S3; 19.2 versions prior to 19.2R3-S1; 19.3 versions prior to 19.3R2-S5, 19.3R3-S1; 19.4 versions prior to 19.4R1-S3, 19.4R2-S3, 19.4R3; 20.1 versions prior to 20.1R2; 20.2 versions prior to 20.2R1-S3 20.2R2; 20.3 versions prior to 20.3R1-S1, 20.3R2. Junos OS Evolved: All versions prior to 20.3R1-S1-EVO, 20.3R2-EVO.

Credit: sirt@juniper.net

Affected SoftwareAffected VersionHow to fix
Junos OS Evolved=17.3
Junos OS Evolved=17.3-r1-s1
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-r2-s5
Junos OS Evolved=17.3-r3
Junos OS Evolved=17.3-r3-s1
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-s7
Junos OS Evolved=17.3-r3-s8
Junos OS Evolved=17.3-r3-s9
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-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-s10
Junos OS Evolved=17.4-r2-s11
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=17.4-r2-s9
Junos OS Evolved=17.4-r3
Junos OS Evolved=17.4-r3-s1
Junos OS Evolved=17.4-r3-s2
Junos OS Evolved=17.4-r3-s3
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-s10
Junos OS Evolved=18.1-r3-s11
Junos OS Evolved=18.1-r3-s2
Junos OS Evolved=18.1-r3-s3
Junos OS Evolved=18.1-r3-s4
Junos OS Evolved=18.1-r3-s6
Junos OS Evolved=18.1-r3-s7
Junos OS Evolved=18.1-r3-s8
Junos OS Evolved=18.1-r3-s9
Junos OS Evolved=18.2
Junos OS Evolved=18.2-r1
Junos OS Evolved=18.2-r1
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=18.2-r2-s6
Junos OS Evolved=18.2-r2-s7
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-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=18.3-r2-s3
Junos OS Evolved=18.3-r2-s4
Junos OS Evolved=18.3-r3
Junos OS Evolved=18.3-r3-s1
Junos OS Evolved=18.3-r3-s2
Junos OS Evolved=18.3-r3-s3
Junos OS Evolved=18.4
Junos OS Evolved=18.4-r1
Junos OS Evolved=18.4-r1-s1
Junos OS Evolved=18.4-r1-s2
Junos OS Evolved=18.4-r1-s3
Junos OS Evolved=18.4-r1-s4
Junos OS Evolved=18.4-r1-s5
Junos OS Evolved=18.4-r1-s6
Junos OS Evolved=18.4-r1-s7
Junos OS Evolved=18.4-r2
Junos OS Evolved=18.4-r2-s1
Junos OS Evolved=18.4-r2-s2
Junos OS Evolved=18.4-r2-s3
Junos OS Evolved=18.4-r2-s4
Junos OS Evolved=18.4-r2-s5
Junos OS Evolved=18.4-r3
Junos OS Evolved=18.4-r3-s1
Junos OS Evolved=18.4-r3-s2
Junos OS Evolved=18.4-r3-s3
Junos OS Evolved=18.4-r3-s4
Junos OS Evolved=18.4-r3-s5
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=19.1-r1-s4
Junos OS Evolved=19.1-r1-s5
Junos OS Evolved=19.1-r2
Junos OS Evolved=19.1-r2-s1
Junos OS Evolved=19.1-r3
Junos OS Evolved=19.1-r3-s1
Junos OS Evolved=19.1-r3-s2
Junos OS Evolved=19.2
Junos OS Evolved=19.2-r1
Junos OS Evolved=19.2-r1-s1
Junos OS Evolved=19.2-r1-s2
Junos OS Evolved=19.2-r1-s3
Junos OS Evolved=19.2-r1-s4
Junos OS Evolved=19.2-r2
Junos OS Evolved=19.2-r3
Junos OS Evolved=19.3
Junos OS Evolved=19.3-r1
Junos OS Evolved=19.3-r1-s1
Junos OS Evolved=19.3-r2
Junos OS Evolved=19.3-r2-s1
Junos OS Evolved=19.3-r2-s2
Junos OS Evolved=19.3-r2-s3
Junos OS Evolved=19.3-r2-s4
Junos OS Evolved=19.3-r3
Junos OS Evolved=19.4-r1
Junos OS Evolved=19.4-r1-s1
Junos OS Evolved=19.4-r1-s2
Junos OS Evolved=19.4-r2
Junos OS Evolved=19.4-r2-s1
Junos OS Evolved=19.4-r2-s2
Junos OS Evolved=20.1-r1
Junos OS Evolved=20.1-r1-s1
Junos OS Evolved=20.1-r1-s2
Junos OS Evolved=20.1-r1-s3
Junos OS Evolved=20.2-r1
Junos OS Evolved=20.2-r1-s1
Junos OS Evolved=20.2-r1-s2
Junos OS Evolved=20.3-r1
Juniper JUNOS=19.2-r1
Juniper JUNOS=19.2-r2
Juniper JUNOS=19.3-r2
Juniper JUNOS=19.4-r1
Juniper JUNOS=19.4-r2
Juniper JUNOS=19.4-r2-s1
Juniper JUNOS=20.1
Juniper JUNOS=20.1-r1
Juniper JUNOS=20.2
Juniper JUNOS=20.3-r1
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-d200
Junos OS Evolved=15.1x49-d210
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
Junos OS Evolved=15.1x49-d30
Junos OS Evolved=15.1x49-d60
Junos OS Evolved=15.1x49-d140
Junos OS Evolved=15.1x49-d150
Junos OS Evolved=15.1x49-d160
Juniper SRX100
Juniper SRX110
Juniper SRX1400
Juniper SRX1500
Juniper SRX210
Juniper SRX220
Juniper SRX240
Juniper SRX240H2
Juniper SRX300
Juniper SRX320
Juniper SRX340
Juniper SRX3400
Juniper SRX345
Juniper SRX3600
Juniper SRX380
Juniper SRX4000
Juniper SRX4100
Juniper SRX4200
Juniper SRX4600
Junos OS SRX 5000 Series
Juniper SRX5400
Juniper SRX550
Juniper SRX550
Juniper SRX550
Juniper SRX5600
Juniper SRX5800
Juniper SRX650
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-s10
Junos OS Evolved=15.1-r7-s11
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=15.1-r7-s6
Junos OS Evolved=15.1-r7-s7
Juniper EX Series
Juniper EX2200-C
Juniper EX2200
Juniper EX2200
Juniper EX2300-24T
Juniper EX2300-C
Juniper EX2300
Juniper EX3200
Juniper EX3300-VX
Juniper EX3300-VX
Juniper EX3400
Juniper EX Series
Juniper EX4200
Juniper EX4300-24T
Juniper EX4300-24P
Juniper EX4300
Juniper EX4300-24T-S
Juniper EX4300
Juniper EX4300-32F-S
Juniper EX4300
Juniper EX4300-32F-S
Juniper EX4300-48MP
Juniper EX4300-48MP-S
Juniper EX4300-48P
Juniper EX4300-48P
Juniper EX4300-48T-AFI
Juniper EX4300-48TAFI
Juniper EX4300-48TDC
Juniper EX4300-48TDC-AFI
Juniper EX4300-48T-S
Juniper EX4300
Juniper EX4300 Multigigabit
Juniper EX4300-48T-DC-AFI
Juniper EX4300
Juniper EX4300
Juniper EX4300
Juniper EX4400-24X
juniper ex4500-vc
Juniper EX4500
Juniper EX Series
Juniper EX4550
Juniper EX4550
Juniper EX4600
Juniper EX4600
Juniper EX4650
Juniper EX6200
Juniper EX Series
Juniper EX Series
Juniper EX8200
Juniper EX8208
Juniper EX Series
Juniper EX9200
Juniper EX Series
Juniper EX9208
Juniper EX9214
Juniper EX9250
Juniper EX9251
Juniper EX9253

Remedy

The following software releases have been updated to resolve this specific issue: Junos OS: 15.1R7-S8, 15.1X49-D240, 17.3R3-S10, 17.4R2-S12, 17.4R3-S4, 18.1R3-S12, 18.2R2-S8, 18.2R3-S6, 18.3R3-S4, 18.4R1-S8, 18.4R2-S6, 18.4R3-S6, 19.1R2-S2, 19.1R3-S3, 19.2R3-S1, 19.3R2-S5, 19.3R3-S1, 19.4R1-S3, 19.4R2-S3, 19.4R3, 20.1R2, 20.2R1-S3, 20.2R2, 20.3R1-S1, 20.3R2, 20.4R1, and all subsequent releases. Junos OS Evolved: 20.3R1-S1-EVO, 20.3R2-EVO, 20.4R1-EVO, and all subsequent releases.

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Reference Links

Frequently Asked Questions

  • What is the severity of CVE-2021-0211?

    CVE-2021-0211 has been rated as a high-severity vulnerability, posing significant risk to affected systems.

  • How do I fix CVE-2021-0211?

    To fix CVE-2021-0211, update the Juniper Networks Junos OS to the latest patched version that addresses this vulnerability.

  • What systems are impacted by CVE-2021-0211?

    CVE-2021-0211 affects multiple versions of Juniper Networks Junos OS, particularly 17.3, 17.4, and 18.x series.

  • Can CVE-2021-0211 be exploited remotely?

    Yes, CVE-2021-0211 can be exploited remotely by attackers if they send crafted BGP FlowSpec messages.

  • What are the consequences of CVE-2021-0211 exploitation?

    Exploitation of CVE-2021-0211 can lead to unexpected modifications in BGP route advertisements, potentially disrupting network traffic.

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