CVE-2020-1662: Junos OS and Junos OS Evolved: RPD crash due to BGP session flapping.

Published Oct 16, 2020
·
Updated

On Juniper Networks Junos OS and Junos OS Evolved devices, BGP session flapping can lead to a routing process daemon (RPD) crash and restart, limiting the attack surface to configured BGP peers. This issue only affects devices with BGP damping in combination with accepted-prefix-limit configuration. When the issue occurs the following messages will appear in the /var/log/messages: rpd[6046]: %DAEMON-4-BGPPREFIXTHRESHEXCEEDED: XXXX (External AS x): Configured maximum accepted prefix-limit threshold(1800) exceeded for inet6-unicast nlri: 1984 (instance master) rpd[6046]: %DAEMON-3-BGPCEASEPREFIXLIMITEXCEEDED: 2001:x:x:x::2 (External AS x): Shutting down peer due to exceeding configured maximum accepted prefix-limit(2000) for inet6-unicast nlri: 2001 (instance master) rpd[6046]: %DAEMON-4: bgprtmaxprefixescheckcommon:9284: NOTIFICATION sent to 2001:x:x:x::2 (External AS x): code 6 (Cease) subcode 1 (Maximum Number of Prefixes Reached) AFI: 2 SAFI: 1 prefix limit 2000 kernel: %KERN-5: mastershiprelinquishonprocessexit: RPD crashed on master RE. Sending SIGUSR2 to chassisd (5612:chassisd) to trigger RE switchover This issue affects: Juniper Networks Junos OS: 17.2R3-S3; 17.3 version 17.3R3-S3 and later versions, prior to 17.3R3-S8; 17.4 version 17.4R2-S4, 17.4R3 and later versions, prior to 17.4R2-S10, 17.4R3-S2; 18.1 version 18.1R3-S6 and later versions, prior to 18.1R3-S10; 18.2 version 18.2R3 and later versions, prior to 18.2R3-S4; 18.2X75 version 18.2X75-D50, 18.2X75-D60 and later versions, prior to 18.2X75-D53, 18.2X75-D65; 18.3 version 18.3R2 and later versions, prior to 18.3R2-S4, 18.3R3-S2; 18.4 version 18.4R2 and later versions, prior to 18.4R2-S5, 18.4R3-S2; 19.1 version 19.1R1 and later versions, prior to 19.1R2-S2, 19.1R3-S1; 19.2 version 19.2R1 and later versions, prior to 19.2R1-S5, 19.2R2; 19.3 versions prior to 19.3R2-S3, 19.3R3; 19.4 versions prior to 19.4R1-S3, 19.4R2; 20.1 versions prior to 20.1R1-S2, 20.1R2. Juniper Networks Junos OS Evolved prior to 20.1R2-EVO. This issue does not affect Juniper Networks Junos OS versions prior to 17.2R3-S3.

Affected Software

59 affected components
Juniper Junos=17.2-r3-s3
Juniper Junos=17.3-r3-s3
Juniper Junos=17.3-r3-s4
Juniper Junos=17.3-r3-s7
Juniper Junos=17.4-r2-s4
Juniper Junos=17.4-r2-s5
Juniper Junos=17.4-r2-s6
Juniper Junos=17.4-r2-s7
Juniper Junos=17.4-r2-s8
Juniper Junos=17.4-r2-s9
Juniper Junos=17.4-r3
Juniper Junos=17.4-r3-s1
Juniper Junos=18.1-r3-s6
Juniper Junos=18.1-r3-s7
Juniper Junos=18.1-r3-s8
Juniper Junos=18.1-r3-s9
Juniper Junos=18.2-r3
Juniper Junos=18.2-r3-s1
Juniper Junos=18.2-r3-s2
Juniper Junos=18.2-r3-s3
Juniper Junos=18.2x75-d50
Juniper Junos=18.2x75-d51
Juniper Junos=18.2x75-d60
Juniper Junos=18.3-r2
Juniper Junos=18.3-r2-s1
Juniper Junos=18.3-r2-s2
Juniper Junos=18.3-r2-s3
Juniper Junos=18.3-r3
Juniper Junos=18.3-r3-s1
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-r2-s4
Juniper Junos=18.4-r3
Juniper Junos=18.4-r3-s1
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=19.1-r2-s1
Juniper Junos=19.1-r3
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
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=19.4-r1
Juniper Junos=19.4-r1-s1
Juniper Junos=19.4-r1-s2
Juniper Junos=20.1-r1
Juniper Junos=20.1-r1-s1

Remediation

Information

The following software releases have been updated to resolve this specific issue: Junos OS: 17.2R3-S4, 17.3R3-S8, 17.3R3-S9, 17.4R2-S10, 17.4R3-S2, 18.1R3-S10, 18.2R3-S4, 18.2X75-D53, 18.2X75-D65, 18.3R2-S4, 18.3R3-S2, 18.4R2-S5, 18.4R3-S2, 19.1R2-S2, 19.1R3-S1, 19.2R1-S5, 19.2R2, 19.3R2-S3, 19.3R3, 19.4R1-S3, 19.4R2, 20.1R1-S2, 20.1R2, 20.2R1, and all subsequent releases. Junos OS Evolved: 20.1R2-EVO, and all subsequent releases.

Event History

Oct 16, 2020
CVE Published
via MITRE·08:31 PM
Data Sourced
via MITRE·08:31 PM
RemedyDescriptionSeverityWeakness

Frequently Asked Questions

1

What is the severity of CVE-2020-1662?

CVE-2020-1662 has been classified as a medium severity vulnerability.

2

How do I fix CVE-2020-1662?

To mitigate CVE-2020-1662, it is recommended to upgrade to the appropriate patched version of Junos OS as specified by Juniper Networks.

3

What systems are affected by CVE-2020-1662?

CVE-2020-1662 affects various versions of Juniper Networks Junos OS specifically those with BGP damping configured.

4

Does CVE-2020-1662 affect all Juniper devices?

No, CVE-2020-1662 only affects specific Junos OS versions that have BGP damping enabled.

5

What is the impact of CVE-2020-1662?

The impact of CVE-2020-1662 includes potential crashes and restarts of the routing process daemon (RPD), disrupting network operations.

Contact

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