CVE-2021-0299

Junos OS: Kernel crash (vmcore) upon receipt of a malformed IPv6 packet

Description

An Improper Handling of Exceptional Conditions vulnerability in the processing of a transit or directly received malformed IPv6 packet in Juniper Networks Junos OS results in a kernel crash, causing the device to restart, leading to a Denial of Service (DoS). Continued receipt and processing of this packet will create a sustained Denial of Service (DoS) condition. This issue only affects systems with IPv6 configured. Devices with only IPv4 configured are not vulnerable to this issue. This issue affects Juniper Networks Junos OS: 19.4 versions prior to 19.4R3; 20.1 versions prior to 20.1R2; 20.2 versions prior to 20.2R1-S1, 20.2R2. This issue does not affect Juniper Networks Junos OS versions prior to 19.4R1.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: Junos OS 19.4R3, 20.1R2, 20.2R1-S1, 20.2R2, 20.3R1, 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 0.37%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Link Tags
https://kb.juniper.net/JSA11213 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-0299?
CVE-2021-0299 has been scored as a high severity vulnerability.
How to fix CVE-2021-0299?
To fix CVE-2021-0299: The following software releases have been updated to resolve this specific issue: Junos OS 19.4R3, 20.1R2, 20.2R1-S1, 20.2R2, 20.3R1, and all subsequent releases.
Is CVE-2021-0299 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-0299 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-2021-0299?
CVE-2021-0299 affects Juniper Networks Junos OS.
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