CVE-2022-49791
📋 TL;DR
A memory leak vulnerability in the Linux kernel's io_uring subsystem allows attackers to cause resource exhaustion by exploiting multishot accept requests. This affects Linux systems using io_uring for asynchronous I/O operations. The vulnerability can lead to denial of service conditions.
💻 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 →⚠️ Risk & Real-World Impact
Worst Case
Complete system unavailability due to kernel memory exhaustion, potentially requiring system reboot and causing service disruption.
Likely Case
Degraded system performance, increased memory usage, and potential application crashes due to resource constraints.
If Mitigated
Minimal impact with proper monitoring and resource limits in place, though some performance degradation may occur.
🎯 Exploit Status
Exploitation requires local access or ability to trigger specific io_uring operations. No public exploits known at this time.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Fixed in kernel stable trees via commits 0e4626de856ef8f25ecd9c716e76d4f95ce95639 and 91482864768a874c4290ef93b84a78f4f1dac51b
Vendor Advisory: https://git.kernel.org/stable/c/0e4626de856ef8f25ecd9c716e76d4f95ce95639
Restart Required: Yes
Instructions:
1. Update Linux kernel to version containing the fix. 2. Check distribution-specific security advisories. 3. Reboot system after kernel update. 4. Verify fix with kernel version check.
🔧 Temporary Workarounds
Disable io_uring
linuxRemove or disable io_uring module if not required
modprobe -r io_uring
echo 'blacklist io_uring' >> /etc/modprobe.d/blacklist.conf
Limit io_uring usage
linuxRestrict applications from using io_uring through security policies
systemctl disable services using io_uring
Use seccomp to block io_uring syscalls
🧯 If You Can't Patch
- Implement strict resource limits (ulimit, cgroups) to contain memory exhaustion
- Monitor system memory usage and io_uring processes for abnormal patterns
🔍 How to Verify
Check if Vulnerable:
Check kernel version and if io_uring is in use: 'uname -r' and 'lsmod | grep io_uring'Check Version:
uname -rVerify Fix Applied:
Verify kernel version is patched and test io_uring functionality for memory leaks📡 Detection & Monitoring
Log Indicators:
- Kernel OOM (Out of Memory) messages
- Increased memory usage in system logs
- Application crashes related to memory allocation
Network Indicators:
- Service degradation or unavailability
- Increased system resource consumption
SIEM Query:
source="kernel" AND ("out of memory" OR "OOM" OR "memory allocation failure") AND process="io_uring"