CVE-2020-1638: Junos OS & Junos OS Evolved: A specific IPv4 packet can lead to FPC restart.

Published Apr 8, 2020
·
Updated

The FPC (Flexible PIC Concentrator) of Juniper Networks Junos OS and Junos OS Evolved may restart after processing a specific IPv4 packet. Only packets destined to the device itself, successfully reaching the RE through existing edge and control plane filtering, will be able to cause the FPC restart. When this issue occurs, all traffic via the FPC will be dropped. By continuously sending this specific IPv4 packet, an attacker can repeatedly crash the FPC, causing an extended Denial of Service (DoS) condition. This issue can only occur when processing a specific IPv4 packet. IPv6 packets cannot trigger this issue. This issue affects: Juniper Networks Junos OS on MX Series with MPC10E or MPC11E and PTX10001: 19.2 versions prior to 19.2R1-S4, 19.2R2; 19.3 versions prior to 19.3R2-S2, 19.3R3; 19.4 versions prior to 19.4R1-S1, 19.4R2. Juniper Networks Junos OS Evolved on on QFX5220, and PTX10003 series: 19.2-EVO versions; 19.3-EVO versions; 19.4-EVO versions prior to 19.4R2-EVO. This issue does not affect Junos OS versions prior to 19.2R1. This issue does not affect Junos OS Evolved versions prior to 19.2R1-EVO.

Affected Software

44 affected components
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=19.3-r1
Juniper Junos=19.3-r1-s1
Juniper Junos=19.3-r2
Juniper Junos=19.3-r2-s1
Juniper Junos=19.4-r1
Juniper MX10003
Juniper MX2008
Juniper MX2010
Juniper MX2020
Juniper MX240
Juniper MX480
Juniper MX960
Juniper Junos OS Evolved=19.2-r1
Juniper Junos OS Evolved=19.3-r2
Juniper Junos OS Evolved=19.4-r1
Juniper PTX10003
Juniper QFX5220
All of the following
Any of the following
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=19.3-r1
Juniper Junos=19.3-r1-s1
Juniper Junos=19.3-r2
Juniper Junos=19.3-r2-s1
Juniper Junos=19.4-r1
Any of the following
Juniper MX10003
Juniper MX2008
Juniper MX2010
Juniper MX2020
Juniper MX240
Juniper MX480
Juniper MX960
All of the following
Any of the following
Juniper Junos OS Evolved=19.2-r1
Juniper Junos OS Evolved=19.3-r2
Juniper Junos OS Evolved=19.4-r1
Any of the following
Juniper PTX10003
Juniper QFX5220

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade Juniper Networks Junos OS Evolved (QFX5220, PTX10003 series) to a version that resolves this vulnerability.

    Fixed in 19.4R2-EVO
  2. Upgrade

    Upgrade Juniper Networks Junos OS Evolved (QFX5220, PTX10003 series) to a version that resolves this vulnerability.

    Fixed in 20.1R1-EVO
  3. Upgrade

    Upgrade Juniper Networks Junos OS (MX Series with MPC10E or MPC11E and PTX10001) to a version that resolves this vulnerability.

    Fixed in 19.2R1-S4
  4. Upgrade

    Upgrade Juniper Networks Junos OS (MX Series with MPC10E or MPC11E and PTX10001) to a version that resolves this vulnerability.

    Fixed in 19.3R2-S2
  5. Upgrade

    Upgrade Juniper Networks Junos OS (MX Series with MPC10E or MPC11E and PTX10001) to a version that resolves this vulnerability.

    Fixed in 19.4R1-S1
  6. Upgrade

    Upgrade Juniper Networks Junos OS (MX Series with MPC10E or MPC11E and PTX10001) to a version that resolves this vulnerability.

    Fixed in 19.2R2
  7. Upgrade

    Upgrade Juniper Networks Junos OS (MX Series with MPC10E or MPC11E and PTX10001) to a version that resolves this vulnerability.

    Fixed in 19.3R3
  8. Upgrade

    Upgrade Juniper Networks Junos OS (MX Series with MPC10E or MPC11E and PTX10001) to a version that resolves this vulnerability.

    Fixed in 19.4R2
  9. Upgrade

    Upgrade Juniper Networks Junos OS (MX Series with MPC10E or MPC11E and PTX10001) to a version that resolves this vulnerability.

    Fixed in 20.1R1

Event History

Apr 8, 2020
CVE Published
via MITRE·07:26 PM
Data Sourced
via MITRE·07:26 PM
RemedyDescriptionSeverityWeakness
Data Sourced
via NVD·08:15 PM
DescriptionSeverityWeaknessAffected Software
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Frequently Asked Questions

1

What is the severity of CVE-2020-1638?

The severity of CVE-2020-1638 is high, with a severity value of 7.5.

2

How does CVE-2020-1638 affect Juniper Networks Junos OS and Junos OS Evolved?

CVE-2020-1638 may cause the FPC (Flexible PIC Concentrator) to restart after processing a specific IPv4 packet in Juniper Networks Junos OS and Junos OS Evolved.

3

Which versions of Juniper Networks Junos OS and Junos OS Evolved are affected by CVE-2020-1638?

The following versions of Juniper Networks Junos OS and Junos OS Evolved are affected: 19.2, 19.2-r1, 19.2-r1-s1, 19.2-r1-s2, 19.2-r1-s3, 19.3-r1, 19.3-r1-s1, 19.3-r2, 19.3-r2-s1, 19.4-r1, 19.2-r1 (Junos OS Evolved), 19.3-r2 (Junos OS Evolved), and 19.4-r1 (Junos OS Evolved).

4

How can I fix CVE-2020-1638?

To fix CVE-2020-1638, it is recommended to upgrade to a non-vulnerable version of Juniper Networks Junos OS or Junos OS Evolved.

5

Where can I find more information about CVE-2020-1638?

More information about CVE-2020-1638 can be found at the following reference: [https://kb.juniper.net/JSA11019](https://kb.juniper.net/JSA11019).

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