CVE-2021-0214

Junos OS: Denial of Service in ppmd upon receipt of malformed packet

MEDIUM

6.5

CVSS Score

Published: April 22, 2021 at 07:36 PM UTC

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

1 product affected across 1 vendorJunos

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Severity

MEDIUM6.5

Exploit prediction

EPSS 0.5%

Description

A vulnerability in the distributed or centralized periodic packet management daemon (PPMD) of Juniper Networks Junos OS may cause receipt of a malformed packet to crash and restart the PPMD process, leading to network destabilization, service interruption, and a Denial of Service (DoS) condition. Continued receipt and processing of these malformed packets will repeatedly crash the PPMD process and sustain the Denial of Service (DoS) condition. Due to the nature of the specifically crafted packet, exploitation of this issue requires direct, adjacent connectivity to the vulnerable component. This issue affects Juniper Networks Junos OS: 17.3 versions prior to 17.3R3-S11; 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-S7; 18.3 versions prior to 18.3R3-S4; 18.4 versions prior to 18.4R1-S8, 18.4R2-S7, 18.4R3-S6; 19.1 versions prior to 19.1R1-S6, 19.1R2-S2, 19.1R3-S4; 19.2 versions prior to 19.2R1-S5, 19.2R3-S1; 19.3 versions prior to 19.3R2-S5, 19.3R3-S1; 19.4 versions prior to 19.4R2-S2, 19.4R3; 20.1 versions prior to 20.1R2; 20.2 versions prior to 20.2R1-S2, 20.2R2.

Affected

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

Junos · Juniper Networks

95%

17.3 ≤ v < 17.3R3-S1117.4 ≤ v < 17.4R2-S12, 17.4R3-S418.1 ≤ v < 18.1R3-S1218.2 ≤ v < 18.2R2-S8, 18.2R3-S718.3 ≤ v < 18.3R3-S418.4 ≤ v < 18.4R1-S8, 18.4R2-S7, 18.4R3-S619.1 ≤ v < 19.1R1-S6, 19.1R2-S2, 19.1R3-S419.2 ≤ v < 19.2R1-S5, 19.2R3-S119.3 ≤ v < 19.3R2-S5, 19.3R3-S119.4 ≤ v < 19.4R2-S2, 19.4R320.1 ≤ v < 20.1R220.2 ≤ v < 20.2R1-S2, 20.2R217.3 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-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 17.4 17.4 r1 17.4 r1-s1 17.4 r1-s2 17.4 r1-s3 17.4 r1-s4 17.4 r1-s5 17.4 r1-s6 17.4 r1-s7 17.4 r2 17.4 r2-s1 17.4 r2-s10 17.4 r2-s11 17.4 r2-s2 17.4 r2-s3 17.4 r2-s4 17.4 r2-s5 17.4 r2-s6 17.4 r2-s7 17.4 r2-s8 17.4 r2-s9 17.4 r3 17.4 r3-s1 17.4 r3-s2 17.4 r3-s3 18.1 18.1 r1 18.1 r2 18.1 r2-s1 18.1 r2-s2 18.1 r2-s4 18.1 r3 18.1 r3-s1 18.1 r3-s10 18.1 r3-s11 18.1 r3-s2 18.1 r3-s3 18.1 r3-s4 18.1 r3-s5 18.1 r3-s6 18.1 r3-s7 18.1 r3-s8 18.1 r3-s9 18.2 18.2 r1 18.2 r1-s2 18.2 r1-s3 18.2 r1-s4 18.2 r1-s5 18.2 r2 18.2 r2-s1 18.2 r2-s2 18.2 r2-s3 18.2 r2-s4 18.2 r2-s5 18.2 r2-s6 18.2 r2-s7 18.2 r3 18.2 r3-s1 18.2 r3-s2 18.2 r3-s3 18.2 r3-s4 18.2 r3-s5 18.2 r3-s6 18.3 18.3 r1 18.3 r1-s1 18.3 r1-s2 18.3 r1-s3 18.3 r1-s4 18.3 r1-s5 18.3 r1-s6 18.3 r2 18.3 r2-s1 18.3 r2-s2 18.3 r2-s3 18.3 r2-s4 18.3 r3 18.3 r3-s1 18.3 r3-s2 18.3 r3-s3 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 r3 18.4 r3-s1 18.4 r3-s2 18.4 r3-s3 18.4 r3-s4 18.4 r3-s5 19.1 19.1 r1 19.1 r1-s1 19.1 r1-s2 19.1 r1-s3 19.1 r1-s4 19.1 r1-s5 19.1 r2 19.1 r2-s1 19.1 r3 19.1 r3-s1 19.1 r3-s2 19.1 r3-s3 19.2 19.2 r1 19.2 r1-s1 19.2 r1-s2 19.2 r1-s3 19.2 r1-s4 19.2 r3 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 r3 19.4 19.4 r1 19.4 r1-s1 19.4 r1-s2 19.4 r2 19.4 r2-s1 19.4 r2-s2 20.1 20.1 r1 20.1 r1-s1 20.1 r1-s2 20.1 r1-s3 20.1 r1-s4 20.2 20.2 r1 20.2 r1-s1

Affected range stops below 17.3R3-S11, so it looks safe — our inference, not a vendor statement

Affected range stops below 17.4R2-S12, 17.4R3-S4, so it looks safe — our inference, not a vendor statement

Affected range stops below 18.1R3-S12, so it looks safe — our inference, not a vendor statement

Affected range stops below 18.2R2-S8, 18.2R3-S7, so it looks safe — our inference, not a vendor statement

Affected range stops below 18.3R3-S4, so it looks safe — our inference, not a vendor statement

Affected range stops below 18.4R1-S8, 18.4R2-S7, 18.4R3-S6, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.1R1-S6, 19.1R2-S2, 19.1R3-S4, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.2R1-S5, 19.2R3-S1, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.3R2-S5, 19.3R3-S1, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.4R2-S2, 19.4R3, so it looks safe — our inference, not a vendor statement

Affected range stops below 20.1R2, so it looks safe — our inference, not a vendor statement

Affected range stops below 20.2R1-S2, 20.2R2, 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/JSA11117

References (1)

x_refsource_MISCVendor Advisory

Source: [email protected]

https://kb.juniper.net/JSA11117

CVSS

6.5MEDIUMjuniper

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

Vector?

Quick Info

StatusMODIFIED

CWE

CWE-20

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