CVE-2023-53633
📋 TL;DR
This CVE describes a memory leak vulnerability in the Linux kernel's QAIC accelerator driver. When the get_user_pages_fast() function fails to allocate all requested pages, the existing code doesn't properly release partially allocated pages, leading to memory exhaustion over time. This affects systems using QAIC accelerator hardware with vulnerable kernel versions.
💻 Affected Systems
- Linux kernel with QAIC accelerator driver
📦 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 →⚠️ Risk & Real-World Impact
Worst Case
Sustained exploitation could lead to kernel memory exhaustion, causing system instability, denial of service, or potential kernel crashes.
Likely Case
Gradual memory consumption leading to performance degradation and eventual system instability requiring reboot.
If Mitigated
Minimal impact with proper monitoring and memory limits in place.
🎯 Exploit Status
Requires local access and ability to trigger map_user_pages() function with specific conditions.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Kernel versions containing fixes from stable commits 73274c33d961f4aa0f968f763e2c9f4210b4f4a3 and cdcba752a3d48fbe6f05cf2c91ab9497c8daad0c
Vendor Advisory: https://git.kernel.org/stable/c/73274c33d961f4aa0f968f763e2c9f4210b4f4a3
Restart Required: Yes
Instructions:
1. Update Linux kernel to version containing the fix. 2. Reboot system to load patched kernel. 3. Verify QAIC driver is functioning correctly post-update.
🔧 Temporary Workarounds
Disable QAIC driver
linuxPrevent loading of vulnerable QAIC accelerator driver
echo 'blacklist qaic' >> /etc/modprobe.d/blacklist.conf
rmmod qaic
Restrict user access
linuxLimit access to QAIC device files to trusted users only
chmod 600 /dev/qaic*
chown root:root /dev/qaic*
🧯 If You Can't Patch
- Implement strict memory monitoring and alerting for abnormal consumption patterns
- Restrict access to QAIC devices to minimal required users and applications
🔍 How to Verify
Check if Vulnerable:
Check kernel version and verify if QAIC driver is loaded: 'lsmod | grep qaic' and 'uname -r'Check Version:
uname -rVerify Fix Applied:
Verify kernel version is updated and QAIC driver functions normally without memory leaks📡 Detection & Monitoring
Log Indicators:
- Kernel OOM (Out of Memory) messages
- Abnormal memory consumption in /proc/meminfo
- QAIC driver error messages
Network Indicators:
- None - local vulnerability only
SIEM Query:
source="kernel" AND ("Out of memory" OR "oom" OR "memory allocation failure") AND process="qaic"