CVE-2023-53088
📋 TL;DR
This is a use-after-free vulnerability in the Linux kernel's MPTCP implementation that occurs during listener shutdown. Attackers could potentially exploit this to cause kernel crashes, denial of service, or potentially execute arbitrary code. Systems running affected Linux kernel versions with MPTCP 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 →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, potential privilege escalation to kernel-level code execution, or system instability requiring reboot.
Likely Case
Kernel crash or denial of service affecting network connectivity and system stability, potentially requiring system reboot.
If Mitigated
No impact if MPTCP is disabled or system is patched.
🎯 Exploit Status
Exploitation requires local access or ability to trigger MPTCP listener shutdown. The vulnerability was discovered through fuzzing and reported with detailed stack traces.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Linux kernel with commits 0a3f4f1f9c27215e4ddcd312558342e57b93e518, 0f4f4cf5d32f10543deb946a37111e714579511e, and 5564be74a22a61855f8b8c100d8c4abb003bb792
Vendor Advisory: https://git.kernel.org/stable/c/0a3f4f1f9c27215e4ddcd312558342e57b93e518
Restart Required: Yes
Instructions:
1. Update Linux kernel to version containing the fix commits. 2. For distributions: Use package manager to update kernel package. 3. Reboot system to load new kernel.
🔧 Temporary Workarounds
Disable MPTCP
linuxDisable Multipath TCP functionality if not required
sysctl -w net.mptcp.enabled=0
echo 'net.mptcp.enabled = 0' >> /etc/sysctl.conf
sysctl -p
🧯 If You Can't Patch
- Disable MPTCP using sysctl commands
- Restrict access to systems to prevent unauthorized users from triggering the vulnerability
🔍 How to Verify
Check if Vulnerable:
Check kernel version and if MPTCP is enabled: uname -r && sysctl net.mptcp.enabledCheck Version:
uname -rVerify Fix Applied:
Verify kernel version is updated and MPTCP is either disabled or patched version is running📡 Detection & Monitoring
Log Indicators:
- Kernel panic logs
- KASAN reports of use-after-free in mptcp functions
- System crash/reboot events
Network Indicators:
- Unexpected network service disruptions
- MPTCP connection failures
SIEM Query:
event_type:kernel_panic OR event_type:system_crash AND (mptcp OR "use-after-free")