CVE-2021-0237

Junos OS: EX4300-MP/EX4600/EX4650/QFX5K Series: Packet Forwarding Engine manager (FXPC) process crashes when deployed in a Virtual Chassis (VC) configuration

Description

On Juniper Networks EX4300-MP Series, EX4600 Series, EX4650 Series, QFX5K Series deployed as a Virtual Chassis with a specific Layer 2 circuit configuration, Packet Forwarding Engine manager (FXPC) process may crash and restart upon receipt of specific layer 2 frames. Continued receipt and processing of this packet will create a sustained Denial of Service (DoS) condition. This issue affects: Juniper Networks Junos OS on EX4300-MP Series, EX4600 Series, EX4650 Series, QFX5K Series 15.1 versions prior to 15.1R7-S9; 17.3 versions prior to 17.3R3-S11; 17.4 versions prior to 17.4R2-S13, 17.4R3-S4, 17.4R3-S5; 18.2 versions prior to 18.2R3-S8; 18.3 versions prior to 18.3R3-S4; 18.4 versions prior to 18.4R2-S7, 18.4R3-S6; 19.1 versions prior to 19.1R3-S4; 19.2 versions prior to 19.2R1-S6, 19.2R3-S1; 19.3 versions prior to 19.3R3-S1; 19.4 versions prior to 19.4R2-S4, 19.4R3-S1; 20.1 versions prior to 20.1R2; 20.2 versions prior to 20.2R2, 20.2R3; 20.3 versions prior to 20.3R1-S2, 20.3R2;

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: 15.1R7-S9, 17.3R3-S11, 17.4R2-S13, 17.4R3-S4, 17.4R3-S5, 18.3R3-S4, 18.4R2-S7, 18.4R3-S6, 19.1R3-S4, 19.2R1-S6, 19.2R3-S1, 19.3R3-S1, 19.4R2-S4, 19.4R3-S1, 20.1R2, 20.2R2, 20.2R3, 20.3R1-S2, 20.3R2, 20.4R1, and all subsequent releases.

Workaround:

  • There are no viable workarounds for this issue.
6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.08%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Link Tags
https://kb.juniper.net/JSA11132 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-0237?
CVE-2021-0237 has been scored as a medium severity vulnerability.
How to fix CVE-2021-0237?
To fix CVE-2021-0237: The following software releases have been updated to resolve this specific issue: 15.1R7-S9, 17.3R3-S11, 17.4R2-S13, 17.4R3-S4, 17.4R3-S5, 18.3R3-S4, 18.4R2-S7, 18.4R3-S6, 19.1R3-S4, 19.2R1-S6, 19.2R3-S1, 19.3R3-S1, 19.4R2-S4, 19.4R3-S1, 20.1R2, 20.2R2, 20.2R3, 20.3R1-S2, 20.3R2, 20.4R1, and all subsequent releases.
Is CVE-2021-0237 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-0237 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-2021-0237?
CVE-2021-0237 affects Juniper Networks Junos OS.
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