CVE-2025-38475
📋 TL;DR
A type confusion vulnerability in the Linux kernel's SMC (Shared Memory Communications) subsystem allows non-INET sockets to incorrectly reuse INET socket infrastructure. This can lead to kernel memory corruption, crashes, or potential privilege escalation. Systems running affected Linux kernel versions with SMC enabled are vulnerable.
💻 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 →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 →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 →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 memory corruption leading to privilege escalation, denial of service, or arbitrary code execution in kernel context.
Likely Case
Kernel panic or system crash causing denial of service, potentially requiring system reboot.
If Mitigated
Limited impact if SMC is disabled or systems are not using affected kernel versions.
🎯 Exploit Status
Exploitation requires triggering specific socket operations. The vulnerability was discovered through syzkaller fuzzing.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Kernel versions with commits 5b02e397929e5b13b969ef1f8e43c7951e2864f5, 60ada4fe644edaa6c2da97364184b0425e8aeaf5, or 67a167a6b8b45607bc34aa541d1c75097d18d460
Vendor Advisory: https://git.kernel.org/stable/c/5b02e397929e5b13b969ef1f8e43c7951e2864f5
Restart Required: Yes
Instructions:
1. Update Linux kernel to patched version. 2. Reboot system. 3. Verify kernel version matches patched release.
🔧 Temporary Workarounds
Disable SMC module
linuxPrevent loading of SMC kernel module to mitigate vulnerability
echo 'install smc /bin/false' >> /etc/modprobe.d/disable-smc.conf
rmmod smc 2>/dev/null || true
update-initramfs -u
Blacklist SMC module
linuxBlacklist SMC module from being loaded
echo 'blacklist smc' >> /etc/modprobe.d/blacklist-smc.conf
update-initramfs -u
🧯 If You Can't Patch
- Disable SMC functionality via kernel command line or module blacklisting
- Restrict access to systems to trusted users only and monitor for crash logs
🔍 How to Verify
Check if Vulnerable:
Check if SMC module is loaded: lsmod | grep smc. Check kernel version against affected ranges.Check Version:
uname -rVerify Fix Applied:
Verify kernel version includes fix commits. Check dmesg for absence of related crash reports.📡 Detection & Monitoring
Log Indicators:
- Kernel panic logs mentioning cipso_v4_sock_setattr, kvfree_call_rcu double-free warnings, SMC-related crashes
Network Indicators:
- Unusual SMC socket creation attempts
SIEM Query:
source="kernel" AND ("cipso_v4_sock_setattr" OR "kvfree_call_rcu" OR "smc" AND "panic")