CVE-2020-1686

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

Description

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.

Remediation

Solution:

  • 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.

Workaround:

  • Standard security best common practices such as limiting packet toward the RE only from trusted networks/host using firewall filter in combination with source address anti-spoofing should be applied to reduce the risk of exposure.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.55%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Link Tags
https://kb.juniper.net/JSA11083 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2020-1686?
CVE-2020-1686 has been scored as a high severity vulnerability.
How to fix CVE-2020-1686?
To fix CVE-2020-1686: 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.
Is CVE-2020-1686 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2020-1686 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2020-1686?
CVE-2020-1686 affects Juniper Networks Junos OS.
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