CVE-2023-52690
📋 TL;DR
This CVE describes a NULL pointer dereference vulnerability in the Linux kernel's powerpc/powernv subsystem. If kasprintf() fails to allocate memory and returns NULL, the scom_debug_init_one() function could dereference this NULL pointer, potentially causing a kernel panic or system crash. This affects systems running Linux kernels with PowerPC PowerNV platform support.
💻 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
Kernel panic leading to system crash and denial of service, requiring physical or remote console access to reboot the system.
Likely Case
System crash or kernel panic when the specific scom_debug_init_one() function is called with memory allocation failure conditions.
If Mitigated
Minor system instability or crash only under specific memory-constrained conditions when accessing SCOM debug functionality.
🎯 Exploit Status
Exploitation requires local access and ability to trigger the vulnerable code path. The vulnerability is a NULL pointer dereference which typically leads to denial of service rather than privilege escalation.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Patches available in stable kernel trees (commits referenced in CVE description)
Vendor Advisory: https://git.kernel.org/stable/c/1eefa93faf69188540b08b024794fa90b1d82e8b
Restart Required: Yes
Instructions:
1. Update to a patched Linux kernel version containing the fix. 2. For distributions: Use package manager to update kernel package. 3. For custom kernels: Apply the patch from the stable kernel tree. 4. Reboot the system to load the new kernel.
🔧 Temporary Workarounds
Disable debugfs access
linuxRestrict access to debugfs which may prevent triggering the vulnerable code path
mount -o remount,nodebugfs /sys/kernel/debug
chmod 000 /sys/kernel/debug
Restrict user access
linuxLimit which users can access system debugging interfaces
chmod 750 /sys/kernel/debug
setfacl -m u:root:rwx /sys/kernel/debug
🧯 If You Can't Patch
- Implement strict access controls to prevent unauthorized users from accessing debugging interfaces
- Monitor system logs for kernel panic events and implement automated alerting
🔍 How to Verify
Check if Vulnerable:
Check kernel version and verify if running on PowerPC PowerNV platform. Examine if the vulnerable code exists in the running kernel.Check Version:
uname -rVerify Fix Applied:
Verify kernel version includes the patched commits. Check that the scom_debug_init_one() function includes NULL pointer check after kasprintf() call.📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages in /var/log/messages or dmesg
- NULL pointer dereference errors in kernel logs
- System crash/reboot events
Network Indicators:
- No network indicators - this is a local vulnerability
SIEM Query:
source="kernel" AND ("NULL pointer dereference" OR "kernel panic" OR "Oops")🔗 References
- https://git.kernel.org/stable/c/1eefa93faf69188540b08b024794fa90b1d82e8b
- https://git.kernel.org/stable/c/2a82c4439b903639e0a1f21990cd399fb0a49c19
- https://git.kernel.org/stable/c/9a260f2dd827bbc82cc60eb4f4d8c22707d80742
- https://git.kernel.org/stable/c/a9c05cbb6644a2103c75b6906e9dafb9981ebd13
- https://git.kernel.org/stable/c/dd8422ff271c22058560832fc3006324ded895a9
- https://git.kernel.org/stable/c/ed8d023cfa97b559db58c0e1afdd2eec7a83d8f2
- https://git.kernel.org/stable/c/f84c1446daa552e9699da8d1f8375eac0f65edc7
- https://git.kernel.org/stable/c/1eefa93faf69188540b08b024794fa90b1d82e8b
- https://git.kernel.org/stable/c/2a82c4439b903639e0a1f21990cd399fb0a49c19
- https://git.kernel.org/stable/c/9a260f2dd827bbc82cc60eb4f4d8c22707d80742
- https://git.kernel.org/stable/c/a9c05cbb6644a2103c75b6906e9dafb9981ebd13
- https://git.kernel.org/stable/c/dd8422ff271c22058560832fc3006324ded895a9
- https://git.kernel.org/stable/c/ed8d023cfa97b559db58c0e1afdd2eec7a83d8f2
- https://git.kernel.org/stable/c/f84c1446daa552e9699da8d1f8375eac0f65edc7
- https://lists.debian.org/debian-lts-announce/2024/06/msg00016.html
