CVE-2023-36845 : What You Need to Know

A PHP External Variable Modification vulnerability in J-Web of Juniper Networks Junos OS on EX Series and SRX Series allows an unauthenticated, network-based attacker to remotely execute code.

Understanding CVE-2023-36845

This CVE involves a critical vulnerability in Junos OS affecting EX Series and SRX Series routers, enabling attackers to execute code remotely.

What is CVE-2023-36845?

A PHP External Variable Modification flaw in Juniper Networks Junos OS on EX and SRX Series allows unauthorized attackers to manipulate PHP execution environments, leading to code injection.

The Impact of CVE-2023-36845

The vulnerability permits unauthenticated, remote code execution, which could result in severe security breaches and compromise sensitive data on affected systems.

Technical Details of CVE-2023-36845

The vulnerability affects Juniper Networks Junos OS versions prior to 20.4R3-S9, 21.1 and later, 21.2 to 22.4, and 23.2, allowing attackers to exploit the flaw through crafted requests.

Vulnerability Description

The flaw in J-Web allows attackers to modify an important environment variable, potentially leading to code injection.

Affected Systems and Versions

EX Series and SRX Series devices running specific Junos OS versions are impacted by this vulnerability.

Exploitation Mechanism

By setting the variable PHPRC in a crafted request, attackers can manipulate PHP execution environments, enabling code injection.

Mitigation and Prevention

It is vital for organizations to take immediate corrective actions to mitigate the risks associated with CVE-2023-36845.

Immediate Steps to Take

Disable J-Web or restrict access to trusted hosts to prevent unauthorized exploitation of the vulnerability.

Long-Term Security Practices

Regularly update Junos OS to the patched versions provided by Juniper Networks to ensure protection against known vulnerabilities.

Patching and Updates

Juniper Networks has released updated software versions to address the CVE-2023-36845 vulnerability. Ensure that affected systems are updated to the latest secure releases.