CVE-2020-1641

Junos OS: A race condition on receipt of crafted LLDP packets leads to a memory leak and an LLDP crash.

Description

A Race Condition vulnerability in Juniper Networks Junos OS LLDP implementation allows an attacker to cause LLDP to crash leading to a Denial of Service (DoS). This issue occurs when crafted LLDP packets are received by the device from an adjacent device. Multiple LACP flaps will occur after LLDP crashes. An indicator of compromise is to evaluate log file details for lldp with RLIMIT. Intervention should occur before 85% threshold of used KB versus maximum available KB memory is reached. show log messages | match RLIMIT | match lldp | last 20 Matching statement is " /kernel: %KERNEL-[number]: Process ([pid #],lldpd) has exceeded 85% of RLIMIT_DATA: " with [] as variable data to evaluate for. This issue affects: Juniper Networks Junos OS: 12.3 versions prior to 12.3R12-S15; 12.3X48 versions prior to 12.3X48-D95; 15.1 versions prior to 15.1R7-S6; 15.1X49 versions prior to 15.1X49-D200; 15.1X53 versions prior to 15.1X53-D593; 16.1 versions prior to 16.1R7-S7; 17.1 versions prior to 17.1R2-S11, 17.1R3-S2; 17.2 versions prior to 17.2R1-S9, 17.2R3-S3; 17.3 versions prior to 17.3R2-S5, 17.3R3-S6; 17.4 versions prior to 17.4R2-S4, 17.4R3; 18.1 versions prior to 18.1R3-S5; 18.2 versions prior to 18.2R2-S7, 18.2R3; 18.2X75 versions prior to 18.2X75-D12, 18.2X75-D33, 18.2X75-D50, 18.2X75-D420; 18.3 versions prior to 18.3R1-S7, 18.3R2-S3, 18.3R3; 18.4 versions prior to 18.4R1-S5, 18.4R2; 19.1 versions prior to 19.1R1-S4, 19.1R2.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: 12.3R12-S15, 12.3X48-D95, 15.1R7-S6, 15.1X49-D200, 15.1X53-D593, 16.1R7-S7, 16.1R7-S7, 17.1R2-S11, 17.1R3-S2, 17.2R1-S9, 17.2R3-S3, 17.3R2-S5, 17.3R3-S6, 17.4R2-S4, 17.4R3, 18.1R3-S5, 18.2R2-S7, 18.2R3, 18.2X75-D33, 18.2X75-D50, 18.2X75-D420, 18.3R1-S7, 18.3R2-S3, 18.3R3, 18.4R1-S5, 18.4R2, 19.1R1-S4, 19.1R2, 19.2R1, and all subsequent releases.

Workaround:

  • Customers may disable LLDP "protocol lldp" or apply firewall filters to block LLDP traffic on ingress interfaces. There are no other known workarounds.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.06%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Link Tags
https://kb.juniper.net/JSA11027 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2020-1641?
CVE-2020-1641 has been scored as a medium severity vulnerability.
How to fix CVE-2020-1641?
To fix CVE-2020-1641: The following software releases have been updated to resolve this specific issue: 12.3R12-S15, 12.3X48-D95, 15.1R7-S6, 15.1X49-D200, 15.1X53-D593, 16.1R7-S7, 16.1R7-S7, 17.1R2-S11, 17.1R3-S2, 17.2R1-S9, 17.2R3-S3, 17.3R2-S5, 17.3R3-S6, 17.4R2-S4, 17.4R3, 18.1R3-S5, 18.2R2-S7, 18.2R3, 18.2X75-D33, 18.2X75-D50, 18.2X75-D420, 18.3R1-S7, 18.3R2-S3, 18.3R3, 18.4R1-S5, 18.4R2, 19.1R1-S4, 19.1R2, 19.2R1, and all subsequent releases.
Is CVE-2020-1641 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2020-1641 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-2020-1641?
CVE-2020-1641 affects Juniper Networks Junos OS.
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