CVE-2023-6606
📋 TL;DR
An out-of-bounds read vulnerability in the Linux kernel's SMB client implementation allows local attackers to read kernel memory. This could lead to system crashes or information disclosure. Only systems with SMB client functionality enabled are affected.
💻 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 →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 causing system crash and denial of service, or sensitive kernel memory disclosure leading to privilege escalation.
Likely Case
System crash/denial of service from kernel panic triggered by memory corruption.
If Mitigated
Minimal impact if proper access controls limit local user privileges and SMB client usage is restricted.
🎯 Exploit Status
Requires local access to trigger the vulnerability through SMB client operations. No public exploit code identified in references.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Multiple kernel versions across different RHEL releases - see specific Red Hat advisories for exact fixed versions.
Vendor Advisory: https://access.redhat.com/errata/RHSA-2024:0723
Restart Required: Yes
Instructions:
1. Check current kernel version with 'uname -r'. 2. Update kernel packages using your distribution's package manager. 3. For RHEL/CentOS: 'sudo yum update kernel' or 'sudo dnf update kernel'. 4. Reboot system to load new kernel.
🔧 Temporary Workarounds
Disable SMB/CIFS client module
linuxPrevent loading of the vulnerable SMB client kernel module
echo 'install cifs /bin/false' >> /etc/modprobe.d/disable-cifs.conf
rmmod cifs 2>/dev/null || true
Restrict local user access
linuxLimit which users can access the system locally to reduce attack surface
🧯 If You Can't Patch
- Implement strict access controls to limit local user privileges
- Monitor for unusual SMB client activity or system crashes
🔍 How to Verify
Check if Vulnerable:
Check kernel version against patched versions in Red Hat advisories: 'uname -r' and compare to affected versions in RHSA-2024:0723, RHSA-2024:0725, etc.Check Version:
uname -rVerify Fix Applied:
Verify kernel version after update matches patched version from advisory: 'uname -r'📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages in /var/log/messages or dmesg
- Unexpected system crashes/reboots
- SMB client related errors
Network Indicators:
- Unusual SMB protocol traffic from local users
SIEM Query:
source="kernel" AND ("panic" OR "Oops" OR "general protection fault") AND process="smb"🔗 References
- https://access.redhat.com/errata/RHSA-2024:0723
- https://access.redhat.com/errata/RHSA-2024:0725
- https://access.redhat.com/errata/RHSA-2024:0881
- https://access.redhat.com/errata/RHSA-2024:0897
- https://access.redhat.com/errata/RHSA-2024:1188
- https://access.redhat.com/errata/RHSA-2024:1248
- https://access.redhat.com/errata/RHSA-2024:1404
- https://access.redhat.com/errata/RHSA-2024:2094
- https://access.redhat.com/security/cve/CVE-2023-6606
- https://bugzilla.kernel.org/show_bug.cgi?id=218218
- https://bugzilla.redhat.com/show_bug.cgi?id=2253611
- https://access.redhat.com/errata/RHSA-2024:0723
- https://access.redhat.com/errata/RHSA-2024:0725
- https://access.redhat.com/errata/RHSA-2024:0881
- https://access.redhat.com/errata/RHSA-2024:0897
- https://access.redhat.com/errata/RHSA-2024:1188
- https://access.redhat.com/errata/RHSA-2024:1248
- https://access.redhat.com/errata/RHSA-2024:1404
- https://access.redhat.com/errata/RHSA-2024:2094
- https://access.redhat.com/security/cve/CVE-2023-6606
- https://bugzilla.kernel.org/show_bug.cgi?id=218218
- https://bugzilla.redhat.com/show_bug.cgi?id=2253611
- https://lists.debian.org/debian-lts-announce/2024/01/msg00004.html
- https://lists.debian.org/debian-lts-announce/2024/06/msg00016.html
