CVE-2021-0280

Junos OS: PTX Series, QFX10K Series: Upon receipt of specific packets BFD sessions might flap due to DDoS policer implementation in Packet Forwarding Engine

Description

Due to an Improper Initialization vulnerability in Juniper Networks Junos OS on PTX platforms and QFX10K Series with Paradise (PE) chipset-based line cards, ddos-protection configuration changes made from the CLI will not take effect as expected beyond the default DDoS (Distributed Denial of Service) settings in the Packet Forwarding Engine (PFE). This may cause BFD sessions to flap when a high rate of specific packets are received. Flapping of BFD sessions in turn may impact routing protocols and network stability, leading to a Denial of Service (DoS) condition. Continued receipt and processing of this packet will create a sustained Denial of Service (DoS) condition. This issue affects only the following platforms with Paradise (PE) chipset-based line cards: PTX1000, PTX3000 (NextGen), PTX5000, PTX10008, PTX10016 Series and QFX10002 Series. This issue affects: Juniper Networks Junos OS 17.4 versions prior to 17.4R3-S5 on PTX Series, QFX10K Series; 18.2 versions prior to 18.2R3-S8 on PTX Series, QFX10K Series; 18.3 versions prior to 18.3R3-S5 on PTX Series, QFX10K Series; 18.4 versions prior to 18.4R2-S8 on PTX Series, QFX10K Series; 19.1 versions prior to 19.1R3-S5 on PTX Series, QFX10K Series; 19.2 versions prior to 19.2R3-S2 on PTX Series, QFX10K Series; 19.3 versions prior to 19.3R3-S2 on PTX Series, QFX10K Series; 19.4 versions prior to 19.4R3-S2 on PTX Series, QFX10K Series; 20.1 versions prior to 20.1R3 on PTX Series, QFX10K Series; 20.2 versions prior to 20.2R2-S3, 20.2R3 on PTX Series, QFX10K Series; 20.3 versions prior to 20.3R2 on PTX Series, QFX10K Series; 20.4 versions prior to 20.4R2 on PTX Series, QFX10K Series.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: Junos OS 17.4R3-S5, 18.2R3-S8, 18.3R3-S5, 18.4R2-S8, 19.1R3-S5, 19.2R3-S2, 19.3R3-S2, 19.4R3-S2, 20.1R3, 20.2R2-S3, 20.2R3, 20.3R2, 20.4R2, 21.1R1, and all subsequent releases.

Workaround:

  • The default ukern policer rate can be reduced by the CLI command: set system ddos-protection protocols bandwidth burst

Category

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

References

Link Tags
https://kb.juniper.net/JSA11184 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-0280?
CVE-2021-0280 has been scored as a high severity vulnerability.
How to fix CVE-2021-0280?
To fix CVE-2021-0280: The following software releases have been updated to resolve this specific issue: Junos OS 17.4R3-S5, 18.2R3-S8, 18.3R3-S5, 18.4R2-S8, 19.1R3-S5, 19.2R3-S2, 19.3R3-S2, 19.4R3-S2, 20.1R3, 20.2R2-S3, 20.2R3, 20.3R2, 20.4R2, 21.1R1, and all subsequent releases.
Is CVE-2021-0280 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-0280 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-2021-0280?
CVE-2021-0280 affects Juniper Networks Junos OS.
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