CVE-2020-1627

Junos OS: vMX and MX150: Denial of Service vulnerability in packet processing

HIGH

7.5

CVSS Score

Published: April 8, 2020 at 07:25 PM UTC

Updated: June 17, 2026 at 03:02 AM UTC

3 products affected across 2 vendorsJunosMx150Vmx

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Severity

HIGH7.5

Exploit prediction

EPSS 1%

Description

A vulnerability in Juniper Networks Junos OS on vMX and MX150 devices may allow an attacker to cause a Denial of Service (DoS) by sending specific packets requiring special processing in microcode that the flow cache can't handle, causing the riot forwarding daemon to crash. By continuously sending the same specific packets, an attacker can repeatedly crash the riot process causing a sustained Denial of Service. Flow cache is specific to vMX based products and the MX150, and is enabled by default in performance mode. This issue can only be triggered by traffic destined to the device. Transit traffic will not cause the riot daemon to crash. When the issue occurs, a core dump and riot log file entry are generated. For example: /var/crash/core.J-UKERN.mpc0.1557255993.3864.gz /home/pfe/RIOT logs: fpc0 riot[1888]: PANIC in lu_reorder_send_packet_postproc(): fpc0 riot[6655]: PANIC in lu_reorder_send_packet_postproc(): This issue affects Juniper Networks Junos OS: 18.1 versions prior to 18.1R3 on vMX and MX150; 18.2 versions prior to 18.2R3 on vMX and MX150; 18.2X75 versions prior to 18.2X75-D60 on vMX and MX150; 18.3 versions prior to 18.3R3 on vMX and MX150; 18.4 versions prior to 18.4R2 on vMX and MX150; 19.1 versions prior to 19.1R2 on vMX and MX150. This issue does not affect Junos OS versions prior to 18.1R1.

Affected

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

Junos · Juniper Networks

95%

18.1 ≤ v < 18.1R318.2 ≤ v < 18.2R318.2X75 ≤ v < 18.2X75-D6018.3 ≤ v < 18.3R318.4 ≤ v < 18.4R219.1 ≤ v < 19.1R218.1 18.1 r2 18.1 r2-s1 18.1 r2-s2 18.1 r2-s4 18.2 18.2 r1 18.2 r1-s3 18.2 r1-s5 18.2 r2-s1 18.2 r2-s2 18.2 r2-s3 18.2 r2-s4 18.2 r2-s5 18.2 r2-s6 18.2X7518.2x7518.2x75 d20 18.2x75 d30 18.2x75 d40 18.3 18.3 r1 18.3 r1-s1 18.3 r1-s2 18.3 r1-s3 18.3 r1-s5 18.3 r2 18.3 r2-s1 18.3 r2-s2 18.4 18.4 r1 18.4 r1-s1 18.4 r1-s2 18.4 r1-s5 19.1 19.1 r1 19.1 r1-s1 19.1 r1-s2 19.1 r1-s3

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

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

Affected range stops below 18.2X75-D60, so it looks safe — our inference, not a vendor statement

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

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

Affected range stops below 19.1R2, so it looks safe — our inference, not a vendor statement

juniper-mx150 (environment) · juniper-vmx (environment)

Mx150 · Juniperdevice

80%

All versions

Vmx · Juniperdevice

80%

All versions

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/JSA11006

References (1)

x_refsource_CONFIRMVendor Advisory

Source: [email protected]

https://kb.juniper.net/JSA11006

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

NVD-CWE-noinfo

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