high CVSS 7.1

CVE-2025-21741·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: usbnet: ipheth: fix DPE OoB read Fix an out-of-bounds DPE read, limit the number of processed DPEs to the amount that fits into the fixed-size NDP16 header.

Severity
high
Software
Kernel
Fixed in
6.13.3
Published
2025-02-27

Affected versions

From: 6.13

Until: 6.13.3

Fixed in: 6.13.3

How to fix this CVE

Update your Linux kernel to version 6.13.3 or later to patch a critical out-of-bounds memory read vulnerability in the iPhone USB Ethernet driver (ipheth). This vulnerability allows a local attacker with low privileges to read sensitive kernel memory and trigger a denial of service condition. Ensure your distribution's kernel packages are updated as soon as patches become available.

sudo dnf update kernel kernel-devel

Defensia detects this vulnerability

How to check if you are affected

  1. Step 1: Check your kernel version with `uname -r` and compare against the fixed version 6.13.3. If you are on 6.13.0 through 6.13.2, you are vulnerable.
  2. Step 2: Verify if the ipheth driver is loaded by running `lsmod | grep ipheth`. If the output shows the module is loaded, the vulnerable component is present on your system.
  3. Step 3: Search system logs for ipheth-related errors or kernel panics using `sudo dmesg | grep -i ipheth` and `sudo journalctl -u kernel | grep -i ipheth` to identify any exploitation attempts or crashes.
  4. Step 4: After patching, confirm the new kernel version with `uname -r` and verify it shows 6.13.3 or higher. Reboot the system if necessary to load the patched kernel.

FAQ

What is CVE-2025-21741?

CVE-2025-21741 is an out-of-bounds memory read vulnerability in the Linux kernel's iPhone USB Ethernet driver (ipheth) that occurs when processing network data packets. A local attacker can exploit this to read kernel memory and crash the system.

Is CVE-2025-21741 being actively exploited?

No, there are currently no known active exploits in the wild or public proof-of-concept code available for CVE-2025-21741, and it is not listed on the CISA Known Exploited Vulnerabilities catalog.

What versions of Kernel are affected by CVE-2025-21741?

Linux kernel versions 6.13.0 through 6.13.2 are affected. Version 6.13.3 and later contain the fix.

How do I check if my server is vulnerable to CVE-2025-21741?

Run `uname -r` to check your kernel version. If it displays 6.13.0, 6.13.1, or 6.13.2, your system is vulnerable. Additionally, run `lsmod | grep ipheth` to confirm the affected driver is loaded.

Does Defensia detect CVE-2025-21741?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If Kernel is installed on a monitored server, CVE-2025-21741 will appear in your dashboard with remediation steps.

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References

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