CVE-2020-1646

Junos OS and Junos OS Evolved: RPD crash while processing a specific BGP update information.

Description

On Juniper Networks Junos OS and Junos OS Evolved devices, processing a specific UPDATE for an EBGP peer can lead to a routing process daemon (RPD) crash and restart. This issue occurs only when the device is receiving and processing the BGP UPDATE for an EBGP peer. This issue does not occur when the device is receiving and processing the BGP UPDATE for an IBGP peer. However, the offending BGP UPDATE can originally come from an EBGP peer, propagates through the network via IBGP peers without causing crash, then it causes RPD crash when it is processed for a BGP UPDATE towards an EBGP peer. Repeated receipt and processing of the same specific BGP UPDATE can result in an extended Denial of Service (DoS) condition. This issue affects: Juniper Networks Junos OS: 17.3R3-S6, 17.4R2-S7, and 18.1R3-S7. Juniper Networks Junos OS Evolved 19.2R2-EVO and later versions, prior to 19.3R1-EVO. Other Junos OS releases are not affected.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: Junos OS: 17.3R3-S7, 17.4R2-S8, 18.1R3-S8, and all subsequent releases. This fix has been proactively committed to other Junos OS releases that are not vulnerable to this issue. Junos OS Evolved: 19.3R1-EVO and all subsequent releases.

Workaround:

  • There are no available workarounds for this issue.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.39%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Affected: Juniper Networks Junos OS Evolved
Published at:
Updated at:

References

Link Tags
https://kb.juniper.net/JSA11033 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2020-1646?
CVE-2020-1646 has been scored as a high severity vulnerability.
How to fix CVE-2020-1646?
To fix CVE-2020-1646: The following software releases have been updated to resolve this specific issue: Junos OS: 17.3R3-S7, 17.4R2-S8, 18.1R3-S8, and all subsequent releases. This fix has been proactively committed to other Junos OS releases that are not vulnerable to this issue. Junos OS Evolved: 19.3R1-EVO and all subsequent releases.
Is CVE-2020-1646 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2020-1646 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-2020-1646?
CVE-2020-1646 affects Juniper Networks Junos OS, Juniper Networks Junos OS Evolved.
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