medium CVSS 5.5

CVE-2023-52783·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: net: wangxun: fix kernel panic due to null pointer When the device uses a custom subsystem vendor ID, the function wx_sw_init() returns before the memory of 'wx->mac_table' is allocated. The null pointer will causes the kernel panic.

Severity
medium
Software
Kernel
Fixed in
6.6.4
Published
2024-05-21

Affected versions

From: 6.3

Until: 6.6.4

Fixed in: 6.6.4

How to fix this CVE

Update your Linux kernel to version 6.6.4 or later to resolve a null pointer dereference that occurs when Wangxun network devices use custom subsystem vendor IDs. This vulnerability can trigger a kernel panic during device initialization. Systems running kernel versions 6.3 through 6.6.3 should prioritize this update, especially if Wangxun NICs are present in your infrastructure.

sudo dnf update kernel

Defensia detects this vulnerability

How to check if you are affected

  1. Step 1: Check your current kernel version with `uname -r` and compare against the affected range 6.3-6.6.3
  2. Step 2: Verify if Wangxun network devices are installed by running `lspci | grep -i wangxun` or checking `ethtool -i <interface>` for driver information
  3. Step 3: Search kernel logs for panic traces containing 'wx_sw_init' or 'null pointer dereference' using `sudo dmesg | grep -i 'panic\|null pointer\|wx_'`
  4. Step 4: After applying the update, confirm the new kernel version with `uname -r` and verify it shows 6.6.4 or later

FAQ

What is CVE-2023-52783?

CVE-2023-52783 is a kernel vulnerability affecting Wangxun network device drivers where the MAC address table memory is not allocated when devices use custom subsystem vendor IDs, resulting in a null pointer dereference that crashes the kernel.

Is CVE-2023-52783 being actively exploited?

No, this vulnerability is not listed on the CISA Known Exploited Vulnerabilities (KEV) catalog and has no public exploits available. However, it can be triggered locally if a Wangxun NIC with a custom subsystem ID is present.

What versions of Kernel are affected by CVE-2023-52783?

Linux kernel versions 6.3 through 6.6.3 are affected. Kernel 6.6.4 and later versions include the fix.

How do I check if my server is vulnerable to CVE-2023-52783?

Run `uname -r` to check your kernel version. If it shows 6.3.x through 6.6.3, and you have Wangxun network devices (check with `lspci | grep -i wangxun`), your system is vulnerable.

Does Defensia detect CVE-2023-52783?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If the Linux kernel is installed on a monitored server, CVE-2023-52783 will appear in your dashboard with remediation steps.

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References

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