high
7.8
CWE
120 119
Advisory Published
Updated

CVE-2021-0284: Junos OS: Upon receipt of specific sequences of genuine packets destined to the device the kernel will crash and restart (vmcore)

First published: Tue Aug 17 2021(Updated: )

A buffer overflow vulnerability in the TCP/IP stack of Juniper Networks Junos OS allows an attacker to send specific sequences of packets to the device thereby causing a Denial of Service (DoS). By repeatedly sending these sequences of packets to the device, an attacker can sustain the Denial of Service (DoS) condition. The device will abnormally shut down as a result of these sent packets. A potential indicator of compromise will be the following message in the log files: "eventd[13955]: SYSTEM_ABNORMAL_SHUTDOWN: System abnormally shut down" This issue is only triggered by traffic destined to the device. Transit traffic will not trigger this issue. This issue affects: Juniper Networks Junos OS 12.3 versions prior to 12.3R12-S19; 15.1 versions prior to 15.1R7-S10; 17.3 versions prior to 17.3R3-S12; 18.4 versions prior to 18.4R2-S9, 18.4R3-S9; 19.1 versions prior to 19.1R3-S7; 19.2 versions prior to 19.2R1-S7, 19.2R3-S3; 19.3 versions prior to 19.3R2-S7, 19.3R3-S3; 19.4 versions prior to 19.4R3-S5; 20.1 versions prior to 20.1R3-S1; 20.2 versions prior to 20.2R3-S2; 20.3 versions prior to 20.3R3-S1; 20.4 versions prior to 20.4R2-S2, 20.4R3; 21.1 versions prior to 21.1R2; 21.2 versions prior to 21.2R1-S1, 21.2R2.

Credit: sirt@juniper.net

Affected SoftwareAffected VersionHow to fix
Juniper Junos=12.3
Juniper Junos=12.3-r1
Juniper Junos=12.3-r10
Juniper Junos=12.3-r10-s1
Juniper Junos=12.3-r10-s2
Juniper Junos=12.3-r11
Juniper Junos=12.3-r12
Juniper Junos=12.3-r12-s1
Juniper Junos=12.3-r12-s10
Juniper Junos=12.3-r12-s11
Juniper Junos=12.3-r12-s12
Juniper Junos=12.3-r12-s13
Juniper Junos=12.3-r12-s14
Juniper Junos=12.3-r12-s15
Juniper Junos=12.3-r12-s16
Juniper Junos=12.3-r12-s17
Juniper Junos=12.3-r12-s18
Juniper Junos=12.3-r12-s3
Juniper Junos=12.3-r12-s4
Juniper Junos=12.3-r12-s6
Juniper Junos=12.3-r12-s8
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=15.1-r7-s6
Juniper Junos=15.1-r7-s7
Juniper Junos=15.1-r7-s8
Juniper Junos=15.1-r7-s9
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-r2-s5
Juniper Junos=17.3-r3
Juniper Junos=17.3-r3
Juniper Junos=17.3-r3-s1
Juniper Junos=17.3-r3-s10
Juniper Junos=17.3-r3-s11
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=17.3-r3-s7
Juniper Junos=17.3-r3-s8
Juniper Junos=17.3-r3-s9
Juniper Junos=18.4
Juniper Junos=18.4-r1
Juniper Junos=18.4-r1-s1
Juniper Junos=18.4-r1-s2
Juniper Junos=18.4-r1-s3
Juniper Junos=18.4-r1-s4
Juniper Junos=18.4-r1-s5
Juniper Junos=18.4-r1-s6
Juniper Junos=18.4-r1-s7
Juniper Junos=18.4-r2
Juniper Junos=18.4-r2-s1
Juniper Junos=18.4-r2-s2
Juniper Junos=18.4-r2-s3
Juniper Junos=18.4-r2-s4
Juniper Junos=18.4-r2-s5
Juniper Junos=18.4-r2-s6
Juniper Junos=18.4-r2-s7
Juniper Junos=18.4-r2-s8
Juniper Junos=18.4-r3
Juniper Junos=18.4-r3-s1
Juniper Junos=18.4-r3-s2
Juniper Junos=18.4-r3-s3
Juniper Junos=18.4-r3-s4
Juniper Junos=18.4-r3-s5
Juniper Junos=18.4-r3-s6
Juniper Junos=18.4-r3-s7
Juniper Junos=18.4-r3-s8
Juniper Junos=19.2
Juniper Junos=19.2-r1
Juniper Junos=19.2-r1-s1
Juniper Junos=19.2-r1-s2
Juniper Junos=19.2-r1-s3
Juniper Junos=19.2-r1-s4
Juniper Junos=19.2-r1-s5
Juniper Junos=19.2-r1-s6
Juniper Junos=19.2-r2
Juniper Junos=19.2-r2-s1
Juniper Junos=19.2-r3
Juniper Junos=19.2-r3-s1
Juniper Junos=19.2-r3-s2
Juniper Junos=19.3
Juniper Junos=19.3-r1
Juniper Junos=19.3-r1-s1
Juniper Junos=19.3-r2
Juniper Junos=19.3-r2-s1
Juniper Junos=19.3-r2-s2
Juniper Junos=19.3-r2-s3
Juniper Junos=19.3-r2-s4
Juniper Junos=19.3-r2-s5
Juniper Junos=19.3-r3
Juniper Junos=19.3-r3-s1
Juniper Junos=19.3-r3-s2
Juniper Junos=19.4-r1
Juniper Junos=19.4-r1-s1
Juniper Junos=19.4-r1-s2
Juniper Junos=19.4-r1-s3
Juniper Junos=19.4-r2
Juniper Junos=19.4-r2-s1
Juniper Junos=19.4-r2-s2
Juniper Junos=19.4-r2-s3
Juniper Junos=19.4-r3
Juniper Junos=19.4-r3-s1
Juniper Junos=19.4-r3-s2
Juniper Junos=19.4-r3-s3
Juniper Junos=19.4-r3-s4
Juniper Junos=20.1-r1
Juniper Junos=20.1-r1-s1
Juniper Junos=20.1-r1-s2
Juniper Junos=20.1-r1-s3
Juniper Junos=20.1-r1-s4
Juniper Junos=20.1-r2
Juniper Junos=20.1-r2-s1
Juniper Junos=20.1-r2-s2
Juniper Junos=20.1-r3
Juniper Junos=20.2-r1
Juniper Junos=20.2-r1-s1
Juniper Junos=20.2-r1-s2
Juniper Junos=20.2-r1-s3
Juniper Junos=20.2-r2
Juniper Junos=20.2-r2-s1
Juniper Junos=20.2-r2-s2
Juniper Junos=20.2-r2-s3
Juniper Junos=20.2-r3
Juniper Junos=20.2-r3-s1
Juniper Junos=20.3-r1
Juniper Junos=20.3-r1-s1
Juniper Junos=20.3-r2
Juniper Junos=20.3-r2-s1
Juniper Junos=20.3-r3
Juniper Junos=20.4-r1
Juniper Junos=20.4-r1-s1
Juniper Junos=20.4-r2
Juniper Junos=20.4-r2-s1
Juniper Junos=21.1-r1
Juniper Junos=21.1-r1-s1
Juniper Junos=21.2-r1

Remedy

The following software releases have been updated to resolve this specific issue: 12.3R12-S19, 15.1R7-S10, 17.3R3-S12, 18.4R2-S9, 18.4R3-S9, 19.1R3-S7, 19.2R1-S7, 19.2R3-S3, 19.3R2-S7, 19.3R3-S3, 19.4R3-S5, 20.1R3-S1, 20.2R3-S2, 20.3R3-S1, 20.4R2-S2, 20.4R3, 21.1R2, 21.2R1-S1, 21.2R2, 21.3R1, and all subsequent releases.

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Reference Links

Frequently Asked Questions

  • What is the severity of CVE-2021-0284?

    CVE-2021-0284 has been classified as a critical severity vulnerability due to its potential to cause a Denial of Service (DoS) condition.

  • How do I fix CVE-2021-0284?

    To remediate CVE-2021-0284, update your Junos OS to the latest available version that addresses this vulnerability.

  • What types of devices are affected by CVE-2021-0284?

    CVE-2021-0284 affects various versions of Juniper Networks Junos OS, including specific releases within the 12.3, 15.1, 17.3, 18.4, 19.2, 19.3, 19.4, 20.1, 20.2, 20.3, and 21.1 series.

  • What can an attacker do by exploiting CVE-2021-0284?

    An attacker can exploit CVE-2021-0284 by sending specific packet sequences to the affected device, leading to a sustained Denial of Service (DoS) attack.

  • Are there any workarounds for CVE-2021-0284 before applying a patch?

    Currently, the recommended approach is to apply the update for CVE-2021-0284, as no specific workarounds have been documented.

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