CVE-2021-0214: A vulnerability in the distributed or centralized periodic packet management daemon (PPMD) of Juniper Networks Junos OS may cause receipt of a malform...

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.

Metrics

CVSS 3.1

6.5/10

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

0.45%

36.0th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions	Update
Juniper	Junos	17.3	—
Juniper	Junos	17.4	—
Juniper	Junos	18.1	—
Juniper	Junos	18.2	—
Juniper	Junos	18.3	—
Juniper	Junos	18.4	—
Juniper	Junos	19.1	—
Juniper	Junos	19.2	—
Juniper	Junos	19.3	—
Juniper	Junos	19.4	R1
Juniper	Junos	20.1	R1
Juniper	Junos	20.2	R1

References

https://kb.juniper.net/JSA11117Vendor Advisory
https://kb.juniper.net/JSA11117Vendor Advisory

Timeline

Published: Apr 22, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-0214?

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.

How severe is CVE-2021-0214?

CVE-2021-0214 has a CVSS score of 6.5/10 (MEDIUM severity). The EPSS model estimates a 0.45% probability of exploitation in the next 30 days.

How do I fix CVE-2021-0214?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.