CVE-2021-0233

Junos OS: ACX500 Series, ACX4000 Series: Denial of Service due to FFEB crash while processing high rate of specific packets.

Description

A vulnerability in Juniper Networks Junos OS ACX500 Series, ACX4000 Series, may allow an attacker to cause a Denial of Service (DoS) by sending a high rate of specific packets to the device, resulting in a Forwarding Engine Board (FFEB) crash. Continued receipt of these packets will sustain the Denial of Service (DoS) condition. This issue affects Juniper Networks Junos OS on ACX500 Series, ACX4000 Series: 17.4 versions prior to 17.4R3-S2.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: 17.4R3-S2, and all subsequent releases.

Workaround:

  • There are no viable workarounds for this issue.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.54%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Link Tags
https://kb.juniper.net/JSA11128 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-0233?
CVE-2021-0233 has been scored as a high severity vulnerability.
How to fix CVE-2021-0233?
To fix CVE-2021-0233: The following software releases have been updated to resolve this specific issue: 17.4R3-S2, and all subsequent releases.
Is CVE-2021-0233 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-0233 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-0233?
CVE-2021-0233 affects Juniper Networks Junos OS.
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