CVE-2021-0294

Junos OS: QFX5000 Series and EX4600 Series: Enhanced storm control might not work leading to partial Denial of Service

Description

A vulnerability in Juniper Networks Junos OS, which only affects the release 18.4R2-S5, where a function is inconsistently implemented on Juniper Networks Junos QFX5000 Series and EX4600 Series, and if "storm-control enhanced" is configured, can lead to the enhanced storm control filter group not be installed. It will cause storm control not to work hence allowing an attacker to cause high CPU usage or packet loss issues by sending a large amount of broadcast or unknown unicast packets arriving the device. This issue affects Juniper Networks QFX5100, QFX5110, QFX5120, QFX5200, QFX5210, EX4600, and EX4650, and QFX5100 with QFX 5e Series image installed. QFX5130 and QFX5220 are not affected from this issue. This issue affects Juniper Networks Junos OS 18.4R2-S5 on QFX5000 Series and EX4600 Series. No other product or platform is affected by this vulnerability.

Remediation

Solution:

  • The following software releases has been updated to resolve this specific issue: Junos OS 18.4R2-S6.

Workaround:

  • There are no viable workarounds for this issue.

Category

5.3
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.23%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Link Tags
https://kb.juniper.net/JSA11196 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-0294?
CVE-2021-0294 has been scored as a medium severity vulnerability.
How to fix CVE-2021-0294?
To fix CVE-2021-0294: The following software releases has been updated to resolve this specific issue: Junos OS 18.4R2-S6.
Is CVE-2021-0294 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-0294 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-2021-0294?
CVE-2021-0294 affects Juniper Networks Junos OS.
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