CVE-2021-0241 Explained : Impact and Mitigation

Juniper Networks Junos OS platforms can face a denial of service (DoS) issue when the JDHCPD process crashes and restarts due to the receipt of a specific DHCPv6 packet, affecting various versions.

Understanding CVE-2021-0241

This CVE involves a vulnerability in Juniper Networks Junos OS that can lead to a DoS condition due to a specific DHCPv6 packet triggering the JDHCPD process to crash and restart.

What is CVE-2021-0241?

The issue affects Juniper Networks Junos OS platforms configured as DHCPv6 local servers or DHCPv6 Relay Agents, causing the JDHCPD process to crash and restart upon receiving a particular DHCPv6 packet.

The Impact of CVE-2021-0241

The vulnerability can result in a sustained DoS condition as the JDHCPD process repeatedly crashes when processing the specific packets, affecting the availability of affected systems.

Technical Details of CVE-2021-0241

The vulnerability is associated with an improper handling of DHCPv6 packets in Juniper Networks Junos OS, impacting various versions within the 17.3 to 20.3 range.

Vulnerability Description

The vulnerability in JDHCPD process can lead to a crash and restart scenario upon receiving certain DHCPv6 packets, affecting the availability of Juniper Networks Junos OS platforms.

Affected Systems and Versions

Juniper Networks Junos OS versions ranging from 17.3 to 20.3 are impacted by this vulnerability, specifically versions prior to 17.3R3-S11, 17.4R3-S4, 18.1R3-S12, and others.

Exploitation Mechanism

The Juniper Security Incident Response Team (SIRT) has not detected any malicious exploitation of this vulnerability, ensuring no known active attacks exploiting this issue.

Mitigation and Prevention

To address CVE-2021-0241, upgrading to the latest software releases is recommended. Junos OS versions 17.3R3-S11, 17.4R3-S4, 18.1R3-S12, and subsequent releases have been updated to resolve this issue.

Immediate Steps to Take

Users are advised to update their Juniper Networks Junos OS to the patched versions mentioned above to mitigate the risk of experiencing the DoS condition.

Long-Term Security Practices

Continuously monitoring for security updates and promptly applying patches is crucial to maintaining a secure network environment and mitigating potential vulnerabilities like CVE-2021-0241.

Patching and Updates

Regularly check for software updates and security advisories from Juniper Networks to stay informed about the latest releases addressing critical vulnerabilities.