CVE-2023-44176: Stack-based Buffer Overflow Vulnerability in Juniper Networks Junos OS CLI Command

A Stack-based Buffer Overflow vulnerability (CVE-2023-44176) has been discovered in the CLI command of Juniper Networks Junos OS. This vulnerability allows a low privileged attacker to execute specific CLI commands, which can lead to a Denial of Service (DoS) condition. Repeated actions by the attacker will create a sustained DoS condition, bringing the affected system to a standstill.

Exploit Details

The Stack-based Buffer Overflow vulnerability is caused by improper handling of user-supplied input in the CLI command. An attacker with low privileges can exploit this vulnerability by entering a specially crafted CLI command. When the command is executed, it causes a buffer overflow, leading to a DoS condition on the affected device.

Here's a simplified code snippet illustrating the vulnerability

#include <stdio.h>
#include <string.h>

void vulnerable_function(char *input) {
    char buffer[256]; // Buffer with fixed size set to 256
    strcpy(buffer, input); // Copy user-supplied input to the buffer, without checking its size
}

int main(int argc, char *argv[]) {
    if (argc > 1) {
        vulnerable_function(argv[1]);
    } else {
        printf("Usage: %s [input]\n", argv[]);
    }

    return ;
}

In this example, the attacker can input more than 256 characters to trigger a buffer overflow, leading to a possible DoS condition.

Links to Original References

1. Juniper Networks Security Advisory: CVE-2023-44176 - Stack-based Buffer Overflow Vulnerability
2. NIST National Vulnerability Database: CVE-2023-44176

Mitigation

Juniper Networks has released updated versions of Junos OS to address this vulnerability. Users are encouraged to update their devices to the latest available versions listed below:

Conclusion

The Stack-based Buffer Overflow vulnerability (CVE-2023-44176) in the CLI command of Juniper Networks Junos OS poses a significant risk as it allows attackers to execute specific CLI commands leading to Denial of Service. It is crucial for administrators and system owners to apply the necessary security updates to protect their networks from potential exploitation.

Timeline

Published on: 10/13/2023 00:15:11 UTC
Last modified on: 10/17/2023 16:01:28 UTC