CVE-2020-1670

Junos OS: EX4300 Series: High CPU load due to receipt of specific IPv4 packets

Description

On Juniper Networks EX4300 Series, receipt of a stream of specific IPv4 packets can cause Routing Engine (RE) high CPU load, which could lead to network protocol operation issue and traffic interruption. This specific packets can originate only from within the broadcast domain where the device is connected. This issue occurs when the packets enter to the IRB interface. Only IPv4 packets can trigger this issue. IPv6 packets cannot trigger this issue. This issue affects Juniper Networks Junos OS on EX4300 series: 17.3 versions prior to 17.3R3-S9; 17.4 versions prior to 17.4R2-S11, 17.4R3-S2; 18.1 versions prior to 18.1R3-S10; 18.2 versions prior to 18.2R3-S4; 18.3 versions prior to 18.3R2-S4, 18.3R3-S2; 18.4 versions prior to 18.4R2-S4, 18.4R3-S2; 19.1 versions prior to 19.1R2-S2, 19.1R3-S1; 19.2 versions prior to 19.2R1-S5, 19.2R2-S1, 19.2R3; 19.3 versions prior to 19.3R2-S4, 19.3R3; 19.4 versions prior to 19.4R1-S3, 19.4R2; 20.1 versions prior to 20.1R1-S3, 20.1R2.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: 17.3R3-S9, 17.4R2-S11, 17.4R3-S2, 18.1R3-S10, 18.2R3-S4, 18.3R2-S4, 18.3R3-S2, 18.4R2-S4, 18.4R3-S2, 19.1R2-S2, 19.1R3-S1, 19.2R1-S5, 19.2R2-S1, 19.2R3, 19.3R2-S4, 19.3R3, 19.4R1-S3, 19.4R2, 20.1R1-S3, 20.1R2, 20.2R1 and all subsequent releases.

Workaround:

  • There are no viable workarounds for this issue.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.09%
Vendor Advisory juniper.net Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Link Tags
https://kb.juniper.net/ vendor advisory
https://kb.juniper.net/InfoCenter/index?page=content&id=JSA11067&actp=SUBSCRIPTION vendor advisory

Frequently Asked Questions

What is the severity of CVE-2020-1670?
CVE-2020-1670 has been scored as a medium severity vulnerability.
How to fix CVE-2020-1670?
To fix CVE-2020-1670: The following software releases have been updated to resolve this specific issue: 17.3R3-S9, 17.4R2-S11, 17.4R3-S2, 18.1R3-S10, 18.2R3-S4, 18.3R2-S4, 18.3R3-S2, 18.4R2-S4, 18.4R3-S2, 19.1R2-S2, 19.1R3-S1, 19.2R1-S5, 19.2R2-S1, 19.2R3, 19.3R2-S4, 19.3R3, 19.4R1-S3, 19.4R2, 20.1R1-S3, 20.1R2, 20.2R1 and all subsequent releases.
Is CVE-2020-1670 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2020-1670 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2020-1670?
CVE-2020-1670 affects Juniper Networks Junos OS.
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