high
7.8
CWE
415
Advisory Published
Updated

CVE-2020-1686: Junos OS: Kernel crash (vmcore) upon receipt of a malformed IPv6 packet.

First published: Wed Oct 14 2020(Updated: )

On Juniper Networks Junos OS devices, receipt of a malformed IPv6 packet may cause the system to crash and restart (vmcore). This issue can be trigged by a malformed IPv6 packet destined to the Routing Engine. An attacker can repeatedly send the offending packet resulting in an extended Denial of Service condition. Only IPv6 packets can trigger this issue. IPv4 packets cannot trigger this issue. This issue affects Juniper Networks Junos OS 18.4 versions prior to 18.4R2-S4, 18.4R3-S1; 19.1 versions prior to 19.1R2-S1, 19.1R3; 19.2 versions prior to 19.2R1-S5, 19.2R2; 19.3 versions prior to 19.3R2-S4, 19.3R3; 19.4 versions prior to 19.4R1-S3, 19.4R2. This issue does not affect Juniper Networks Junos OS prior to 18.4R1.

Credit: sirt@juniper.net

Affected SoftwareAffected VersionHow to fix
Juniper Junos=18.4
Juniper Junos=18.4-r1
Juniper Junos=18.4-r1-s1
Juniper Junos=18.4-r1-s2
Juniper Junos=18.4-r1-s5
Juniper Junos=18.4-r1-s6
Juniper Junos=18.4-r2
Juniper Junos=18.4-r2-s1
Juniper Junos=18.4-r2-s2
Juniper Junos=18.4-r2-s3
Juniper Junos=18.4-r3
Juniper Junos=19.1
Juniper Junos=19.1-r1
Juniper Junos=19.1-r1-s1
Juniper Junos=19.1-r1-s2
Juniper Junos=19.1-r1-s3
Juniper Junos=19.1-r1-s4
Juniper Junos=19.1-r2
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=19.2-r1-s4
Juniper Junos=19.3
Juniper Junos=19.3-r1
Juniper Junos=19.3-r1-s1
Juniper Junos=19.3-r2
Juniper Junos=19.3-r2-s1
Juniper Junos=19.3-r2-s2
Juniper Junos=19.3-r2-s3
Juniper Junos=19.4-r1
Juniper Junos=19.4-r1-s1
Juniper Junos=19.4-r1-s2

Remedy

The following software releases have been updated to resolve this specific issue: Junos OS 18.4R2-S4, 18.4R3-S1, 19.1R2-S1, 19.1R3, 19.2R1-S5, 19.2R2, 19.3R2-S4, 19.3R3, 19.4R1-S3, 19.4R2, 19.4R2-S1, 20.1R1, and all subsequent releases.

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Reference Links

Frequently Asked Questions

  • What is the severity of CVE-2020-1686?

    The severity of CVE-2020-1686 is classified as critical due to potential system crashes caused by malformed IPv6 packets.

  • How do I fix CVE-2020-1686?

    To fix CVE-2020-1686, upgrade the Junos OS to a version that is not affected, such as versions released after the vulnerability disclosure.

  • Which devices are affected by CVE-2020-1686?

    CVE-2020-1686 affects Juniper Networks Junos OS devices, specifically those running affected versions of Junos OS 18.4 and 19.1 to 19.4.

  • What is the impact of CVE-2020-1686?

    The impact of CVE-2020-1686 is that it can cause a complete system crash and an automatic restart of the affected device.

  • Can CVE-2020-1686 be exploited remotely?

    Yes, CVE-2020-1686 can be exploited remotely via the sending of a specially crafted malformed IPv6 packet to the Routing Engine.

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