CVE-2025-22103
📋 TL;DR
A race condition in the Linux kernel's networking subsystem causes a NULL pointer dereference when deleting L3S mode ipvlan interfaces. This vulnerability can cause kernel panics and system crashes, affecting Linux systems using ipvlan networking in L3S mode.
💻 Affected Systems
- Linux kernel
📦 What is this software?
Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →⚠️ Risk & Real-World Impact
Worst Case
Kernel panic leading to system crash and denial of service, potentially requiring physical access to reboot affected systems.
Likely Case
System crash or kernel panic when ipvlan interfaces in L3S mode are deleted during network traffic processing.
If Mitigated
Minor performance impact or no effect if ipvlan L3S mode is not used.
🎯 Exploit Status
Requires local access to create and delete ipvlan interfaces. Race condition makes timing somewhat unpredictable.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Kernel versions containing fixes from git commits: 0032c99e83b9ce6d5995d65900aa4b6ffb501cce, 52b44d8c653459c658b733d13658afdde45f6836, 59599bce44af3df7a215ebc81cb166426e1c9204, f9dff65140efc289f01bcf39c3ca66a8806b6132
Vendor Advisory: https://git.kernel.org/stable/c/
Restart Required: Yes
Instructions:
1. Update Linux kernel to patched version. 2. Reboot system. 3. Verify kernel version with 'uname -r'. 4. Check if ipvlan modules are loaded with 'lsmod | grep ipvlan'.
🔧 Temporary Workarounds
Avoid ipvlan L3S mode
linuxDo not use ipvlan interfaces in L3S mode until patched.
# Use alternative networking modes
# ip link add link eth0 ipvlan1 type ipvlan mode l2
# Or use bridge/macvlan instead
Restrict network namespace access
linuxLimit who can create/delete network interfaces to trusted administrators only.
# Use Linux capabilities and namespaces restrictions
# setcap cap_net_admin=ep /path/to/trusted_app
# Or use user/group permissions
🧯 If You Can't Patch
- Disable ipvlan L3S mode usage in all containers and network configurations
- Implement strict access controls to prevent unauthorized users from creating/deleting network interfaces
🔍 How to Verify
Check if Vulnerable:
Check if ipvlan L3S interfaces exist: 'ip link show type ipvlan' and verify mode. Check kernel version against affected ranges.Check Version:
uname -rVerify Fix Applied:
After patching, verify kernel version and test ipvlan L3S interface deletion during network traffic.📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages in /var/log/messages or dmesg
- NULL pointer dereference errors mentioning l3mdev_l3_rcv or ipvlan
- System crash/reboot logs
Network Indicators:
- Sudden loss of network connectivity on systems using ipvlan
- Container networking failures
SIEM Query:
source="kernel" AND ("NULL pointer dereference" OR "l3mdev_l3_rcv" OR "ipvlan" OR "kernel panic")