CVE-2023-44466: Linux kernel vulnerability discovered in net/ceph/messenger_v2.c, leading to buffer overflow and remote code execution

Attention Linux kernel users: an issue has recently been discovered in the net/ceph/messenger_v2.c file that could potentially lead to malicious attacks. Specifically, the problem lies with an integer signedness error which causes a buffer overflow, providing the opportunity for remote code execution via HELLO or one of the AUTH frames. This vulnerability, referred to as CVE-2023-44466, is applicable for Linux kernel versions before 6.4.5.

The root of this vulnerability is the lack of proper validation of an untrusted length from a TCP packet in the ceph_decode_32 function in the affected file. As a consequence, a malicious attacker can potentially exploit this flaw to execute arbitrary code on the victim's machine.

Here's a snippet of the code in question

static int process_hello(struct ceph_connection *con)
{
    ...
    int proto;
    u32 len;
    ...
    
    ceph_decode_32_safe(&p, end, len, bad);
    if (end - p < len)
        goto bad;
    ...
}

In this code snippet, len is extracted from a TCP packet and considered as a signed 32-bit integer. Since there's no validation of the len variable, it could potentially cause a buffer overflow, which in turn could lead to the execution of arbitrary code by an attacker.

This vulnerability was discovered by security researchers, and the references to the original findings can be found in the following links:
- Link 1: Linux Kernel Mailing List - Fixes signedness issue in process_{hello, auth} (Linux kernel 6.4.5)
- Link 2: *exploit-db* - CVE-2023-44466: Linux kernel net/ceph/messenger_v2.c in versions before 6.4.5 vulnerability

As of now, the exploit details are not widely known. However, researchers have confirmed that the flaw can be exploited by sending crafted HELLO or AUTH frames to the target server, thereby triggering the buffer overflow.

To protect yourself from this vulnerability, it is essential to ensure that the Linux kernel version is updated to at least 6.4.5. Regularly updating your software is crucial to safeguarding your system from common security vulnerabilities.

To conclude, CVE-2023-44466 is a noteworthy vulnerability in the Linux kernel that can potentially impact a significant number of systems. It is crucial to stay informed about the latest security threats and apply security patches in a timely manner. Stay safe and keep your systems updated!

Timeline

Published on: 09/29/2023 06:15:11 UTC
Last modified on: 11/16/2023 16:15:31 UTC