CVE-2023-53131
📋 TL;DR
This CVE describes a memory leak vulnerability in the Linux kernel's SUNRPC server component during shutdown. A race condition can prevent proper cleanup of svc_rqst structures, leading to resource exhaustion. This affects Linux systems using SUNRPC services.
💻 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
Sustained exploitation could lead to kernel memory exhaustion, causing system instability, denial of service, or potential kernel panic.
Likely Case
Memory leak during server shutdown scenarios, potentially causing resource exhaustion over time in systems with frequent RPC service restarts.
If Mitigated
Minimal impact with proper monitoring and restart procedures; memory would be reclaimed on full system reboot.
🎯 Exploit Status
Exploitation requires triggering specific race conditions during server shutdown; no known public exploits.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Kernel versions containing commits: 7a3720361068ab520aed4608bad31ea9a6cc7fe7, 9ca6705d9d609441d34f8b853e1e4a6369b3b171, ad7e40ee157ba33950a4ccdc284334580da3638d, ce7dd61e004002bc1c48d1ca47c887f3f3cc7370, f74b3286859463cd63cc9d4aeaabd8b0c640182a
Vendor Advisory: https://git.kernel.org/stable/c/7a3720361068ab520aed4608bad31ea9a6cc7fe7
Restart Required: Yes
Instructions:
1. Update Linux kernel to patched version from your distribution's repositories. 2. Reboot system to load new kernel. 3. Verify kernel version after reboot.
🔧 Temporary Workarounds
Disable SUNRPC services if not needed
linuxReduce attack surface by disabling unnecessary SUNRPC/RPC services
systemctl disable rpcbind
systemctl stop rpcbind
Check for other RPC services with: systemctl list-units | grep -i rpc
🧯 If You Can't Patch
- Monitor system memory usage and restart SUNRPC services before memory exhaustion occurs
- Implement regular system reboots to clear accumulated memory leaks
🔍 How to Verify
Check if Vulnerable:
Check kernel version and compare with patched versions from distribution vendor. Check if SUNRPC services are running: systemctl status rpcbindCheck Version:
uname -rVerify Fix Applied:
Verify kernel version after update matches patched version. Monitor memory usage during SUNRPC service restarts.📡 Detection & Monitoring
Log Indicators:
- Kernel OOM (Out of Memory) messages in /var/log/kern.log or dmesg
- Increasing memory usage without corresponding process growth
Network Indicators:
- Unusual RPC service restart patterns
SIEM Query:
source="kernel" AND ("out of memory" OR "oom") AND process="rpc"🔗 References
- https://git.kernel.org/stable/c/7a3720361068ab520aed4608bad31ea9a6cc7fe7
- https://git.kernel.org/stable/c/9ca6705d9d609441d34f8b853e1e4a6369b3b171
- https://git.kernel.org/stable/c/ad7e40ee157ba33950a4ccdc284334580da3638d
- https://git.kernel.org/stable/c/ce7dd61e004002bc1c48d1ca47c887f3f3cc7370
- https://git.kernel.org/stable/c/f74b3286859463cd63cc9d4aeaabd8b0c640182a
