CVE-2021-0276 Explained : Impact and Mitigation
Learn about CVE-2021-0276, a critical stack-based Buffer Overflow vulnerability in Juniper Networks SBR Carrier allowing remote code execution (RCE), its impact, affected versions, and mitigation steps.
A stack-based Buffer Overflow vulnerability in Juniper Networks SBR Carrier allows attackers to crash the radius daemon, leading to Denial of Service (DoS) or remote code execution (RCE).
Understanding CVE-2021-0276
This CVE describes a critical vulnerability in Juniper Networks SBR Carrier Edition that can be exploited to execute remote code when EAP Authentication is configured.
What is CVE-2021-0276?
CVE-2021-0276 is a stack-based Buffer Overflow vulnerability in Juniper Networks SBR Carrier Edition that allows attackers to crash the radius daemon, resulting in Denial of Service (DoS) or remote code execution (RCE).
The Impact of CVE-2021-0276
The impact of this vulnerability is considered critical, with a CVSS base score of 9.8 (Critical). Attackers can exploit this flaw to disrupt services and potentially execute arbitrary code remotely.
Technical Details of CVE-2021-0276
This section covers the specifics of the vulnerability, affected systems, and how it can be exploited.
Vulnerability Description
The vulnerability arises when specific packets are sent to the SBR Carrier with EAP authentication configured, causing the radius daemon to crash. This enables attackers to achieve DoS or RCE.
Affected Systems and Versions
Juniper Networks SBR Carrier versions prior to 8.4.1R19, 8.5.0R10, and 8.6.0R4 are affected by this vulnerability.
Exploitation Mechanism
By continuously sending the specific malicious packets, an attacker can consistently crash the radius daemon, leading to sustained Denial of Service (DoS) or possible remote code execution (RCE).
Mitigation and Prevention
To address CVE-2021-0276, consider the following steps and best practices.
Immediate Steps to Take
Ensure that your SBR Carrier instance is updated to one of the patched releases provided by Juniper Networks (8.4.1R19, 8.5.0R10, 8.6.0R4, or later).
Long-Term Security Practices
Regularly update and patch your systems to prevent known vulnerabilities and secure your network infrastructure.
Patching and Updates
Juniper Networks has released updated versions to resolve this issue. It is recommended to apply the patches promptly to mitigate the risk.