CVE-2025-38675
📋 TL;DR
This CVE describes a race condition vulnerability in the Linux kernel's XFRM (IPsec) subsystem where uninitialized memory pointers could be accessed during state lookups. This affects Linux systems using IPsec networking, potentially allowing local attackers to cause kernel crashes or undefined behavior. The vulnerability requires local access to exploit.
💻 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 →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, or potential memory corruption that could be leveraged for privilege escalation.
Likely Case
System instability or kernel crash when IPsec is heavily used with concurrent connections across multiple CPU cores.
If Mitigated
Minimal impact if IPsec is not used or if systems have limited concurrent connections.
🎯 Exploit Status
Requires local access and specific timing conditions (race condition). Exploitation requires understanding of kernel internals and IPsec state management.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Patches available in stable kernel branches (commits: 463562f9591742be62ddde3b426a0533ed496955, 6bf2daafc51bcb9272c0fdff2afd38217337d0d3, 94d077c331730510d5611b438640a292097341f0)
Vendor Advisory: https://git.kernel.org/stable/c/463562f9591742be62ddde3b426a0533ed496955
Restart Required: Yes
Instructions:
1. Update Linux kernel to patched version from your distribution vendor. 2. Reboot system to load new kernel. 3. Verify kernel version after reboot.
🔧 Temporary Workarounds
Disable IPsec/XFRM
LinuxIf IPsec functionality is not required, disable XFRM subsystem to eliminate attack surface
echo 'blacklist xfrm' >> /etc/modprobe.d/blacklist.conf
rmmod xfrm_user xfrm_algo xfrm4_tunnel xfrm6_tunnel xfrm4_mode_tunnel xfrm6_mode_tunnel
🧯 If You Can't Patch
- Restrict local user access to systems using IPsec
- Monitor for kernel panic/crash events and investigate any suspicious local user activity
🔍 How to Verify
Check if Vulnerable:
Check kernel version and compare with patched versions from distribution vendor. Systems using IPsec with kernel versions containing the vulnerable code are affected.Check Version:
uname -rVerify Fix Applied:
Verify kernel version matches patched version from vendor and check that IPsec functionality still works correctly.📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages
- OOPs (kernel crash) logs in /var/log/messages or journalctl
- IPsec connection failures
Network Indicators:
- Sudden loss of IPsec VPN connections
- Increased kernel-related errors
SIEM Query:
source="kernel" AND ("panic" OR "Oops" OR "BUG") AND process="xfrm"