CVE-2021-0284

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

HIGH

7.5

CVSS Score

Published: August 17, 2021 at 10:50 PM UTC

Updated: June 17, 2026 at 03:29 AM UTC

1 product affected across 1 vendorJunos

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Severity

HIGH7.5

Exploit prediction

EPSS 1.0%

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Junos · Juniper Networks

95%

12.3 ≤ v < 12.3R12-S1915.1 ≤ v < 15.1R7-S1017.3 ≤ v < 17.3R3-S1218.4 ≤ v < 18.4R2-S9, 18.4R3-S919.1 ≤ v < 19.1R3-S719.2 ≤ v < 19.2R1-S7, 19.2R3-S319.3 ≤ v < 19.3R2-S7, 19.3R3-S319.4 ≤ v < 19.4R3-S520.1 ≤ v < 20.1R3-S120.2 ≤ v < 20.2R3-S220.3 ≤ v < 20.3R3-S120.4 ≤ v < 20.4R2-S2, 20.4R321.1 ≤ v < 21.1R221.2 ≤ v < 21.2R1-S1, 21.2R212.3 12.3 r1 12.3 r10 12.3 r10-s1 12.3 r10-s2 12.3 r11 12.3 r12 12.3 r12-s1 12.3 r12-s10 12.3 r12-s11 12.3 r12-s12 12.3 r12-s13 12.3 r12-s14 12.3 r12-s15 12.3 r12-s16 12.3 r12-s17 12.3 r12-s18 12.3 r12-s3 12.3 r12-s4 12.3 r12-s6 12.3 r12-s8 15.1 15.1 a1 15.1 f 15.1 f1 15.1 f2 15.1 f2-s1 15.1 f2-s2 15.1 f2-s3 15.1 f2-s4 15.1 f3 15.1 f4 15.1 f5 15.1 f5-s7 15.1 f6 15.1 f6-s1 15.1 f6-s10 15.1 f6-s12 15.1 f6-s2 15.1 f6-s3 15.1 f6-s4 15.1 f6-s5 15.1 f6-s6 15.1 f6-s7 15.1 f6-s8 15.1 f6-s9 15.1 f7 15.1 r 15.1 r1 15.1 r2 15.1 r3 15.1 r4 15.1 r4-s7 15.1 r4-s8 15.1 r4-s9 15.1 r5 15.1 r5-s1 15.1 r5-s3 15.1 r5-s5 15.1 r5-s6 15.1 r6 15.1 r6-s1 15.1 r6-s2 15.1 r6-s3 15.1 r6-s4 15.1 r6-s6 15.1 r7 15.1 r7-s1 15.1 r7-s2 15.1 r7-s3 15.1 r7-s4 15.1 r7-s5 15.1 r7-s6 15.1 r7-s7 15.1 r7-s8 15.1 r7-s9 17.3 17.3 r1 17.3 r1-s1 17.3 r1-s4 17.3 r2 17.3 r2-s1 17.3 r2-s2 17.3 r2-s3 17.3 r2-s4 17.3 r2-s5 17.3 r3 17.3 r3-s1 17.3 r3-s10 17.3 r3-s11 17.3 r3-s2 17.3 r3-s3 17.3 r3-s4 17.3 r3-s5 17.3 r3-s6 17.3 r3-s7 17.3 r3-s8 17.3 r3-s9 18.4 18.4 r1 18.4 r1-s1 18.4 r1-s2 18.4 r1-s3 18.4 r1-s4 18.4 r1-s5 18.4 r1-s6 18.4 r1-s7 18.4 r2 18.4 r2-s1 18.4 r2-s2 18.4 r2-s3 18.4 r2-s4 18.4 r2-s5 18.4 r2-s6 18.4 r2-s7 18.4 r2-s8 18.4 r3 18.4 r3-s1 18.4 r3-s2 18.4 r3-s3 18.4 r3-s4 18.4 r3-s5 18.4 r3-s6 18.4 r3-s7 18.4 r3-s8 19.1 19.2 19.2 r1 19.2 r1-s1 19.2 r1-s2 19.2 r1-s3 19.2 r1-s4 19.2 r1-s5 19.2 r1-s6 19.2 r2 19.2 r2-s1 19.2 r3 19.2 r3-s1 19.2 r3-s2 19.3 19.3 r1 19.3 r1-s1 19.3 r2 19.3 r2-s1 19.3 r2-s2 19.3 r2-s3 19.3 r2-s4 19.3 r2-s5 19.3 r3 19.3 r3-s1 19.3 r3-s2 19.4 19.4 r1 19.4 r1-s1 19.4 r1-s2 19.4 r1-s3 19.4 r2 19.4 r2-s1 19.4 r2-s2 19.4 r2-s3 19.4 r3 19.4 r3-s1 19.4 r3-s2 19.4 r3-s3 19.4 r3-s4 20.1 20.1 r1 20.1 r1-s1 20.1 r1-s2 20.1 r1-s3 20.1 r1-s4 20.1 r2 20.1 r2-s1 20.1 r2-s2 20.1 r3 20.2 20.2 r1 20.2 r1-s1 20.2 r1-s2 20.2 r1-s3 20.2 r2 20.2 r2-s1 20.2 r2-s2 20.2 r2-s3 20.2 r3 20.2 r3-s1 20.3 20.3 r1 20.3 r1-s1 20.3 r2 20.3 r2-s1 20.3 r3 20.4 20.4 r1 20.4 r1-s1 20.4 r2 20.4 r2-s1 21.1 21.1 r1 21.1 r1-s1 21.2 21.2 r1

Affected range stops below 12.3R12-S19, so it looks safe — our inference, not a vendor statement

Affected range stops below 15.1R7-S10, so it looks safe — our inference, not a vendor statement

Affected range stops below 17.3R3-S12, so it looks safe — our inference, not a vendor statement

Affected range stops below 18.4R2-S9, 18.4R3-S9, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.1R3-S7, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.2R1-S7, 19.2R3-S3, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.3R2-S7, 19.3R3-S3, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.4R3-S5, so it looks safe — our inference, not a vendor statement

Affected range stops below 20.1R3-S1, so it looks safe — our inference, not a vendor statement

Affected range stops below 20.2R3-S2, so it looks safe — our inference, not a vendor statement

Affected range stops below 20.3R3-S1, so it looks safe — our inference, not a vendor statement

Affected range stops below 20.4R2-S2, 20.4R3, so it looks safe — our inference, not a vendor statement

Affected range stops below 21.1R2, so it looks safe — our inference, not a vendor statement

Affected range stops below 21.2R1-S1, 21.2R2, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

https://kb.juniper.net/JSA11200

References (1)

x_refsource_CONFIRMVendor Advisory

Source: [email protected]

https://kb.juniper.net/JSA11200

CVSS

7.5HIGHjuniper

Attack Vector: NETWORK
Complexity: LOW
Privileges: NONE
User Interaction: NONE
Scope: UNCHANGED
Confidentiality: NONE
Integrity: NONE
Availability: HIGH

Vector?

Quick Info

StatusMODIFIED

CWE

CWE-120

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