CVE-2021-31376

Junos OS: ACX Series: Packet Forwarding Engine manager (FXPC) process crashes when processing DHCPv6 packets

Description

An Improper Input Validation vulnerability in Packet Forwarding Engine manager (FXPC) process of Juniper Networks Junos OS allows an attacker to cause a Denial of Service (DoS) by sending specific DHCPv6 packets to the device and crashing the FXPC service. Continued receipt and processing of this specific packet will create a sustained Denial of Service (DoS) condition. This issue affects only the following platforms in ACX Series: ACX500, ACX1000, ACX1100, ACX2100, ACX2200, ACX4000, ACX5048, ACX5096 devices. Other ACX platforms are not affected from this issue. This issue affects Juniper Networks Junos OS on ACX500, ACX1000, ACX1100, ACX2100, ACX2200, ACX4000, ACX5048, ACX5096: 18.4 version 18.4R3-S7 and later versions prior to 18.4R3-S8. This issue does not affect: Juniper Networks Junos OS 18.4 versions prior to 18.4R3-S7 on ACX500, ACX1000, ACX1100, ACX2100, ACX2200, ACX4000, ACX5048, ACX5096.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: Junos OS 18.4R3-S8.

Workaround:

  • There are no viable workarounds for this issue.

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/JSA11241 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-31376?
CVE-2021-31376 has been scored as a high severity vulnerability.
How to fix CVE-2021-31376?
To fix CVE-2021-31376: The following software releases have been updated to resolve this specific issue: Junos OS 18.4R3-S8.
Is CVE-2021-31376 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-31376 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-2021-31376?
CVE-2021-31376 affects Juniper Networks Junos OS.
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