CVE-2023-6200
📋 TL;DR
A race condition vulnerability in the Linux kernel's ICMPv6 router advertisement handling allows unauthenticated attackers on adjacent networks to trigger arbitrary code execution. This affects Linux systems with IPv6 enabled, potentially leading to full system compromise. Attackers must be on the same network segment as the target.
💻 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 →⚠️ Risk & Real-World Impact
Worst Case
Full system compromise with root privileges, allowing complete control over the affected system, data theft, and lateral movement.
Likely Case
Denial of service or limited code execution leading to system instability or privilege escalation.
If Mitigated
Minimal impact if proper network segmentation and kernel patches are applied.
🎯 Exploit Status
Exploitation requires race condition timing and adjacent network access. No public exploit code is known at this time.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Linux kernel with commit dade3f6a1e4e or later
Vendor Advisory: https://access.redhat.com/security/cve/CVE-2023-6200
Restart Required: Yes
Instructions:
1. Check your Linux distribution's security advisories. 2. Update kernel packages using your package manager (e.g., 'yum update kernel' for RHEL, 'apt-get update && apt-get upgrade' for Debian/Ubuntu). 3. Reboot the system to load the new kernel.
🔧 Temporary Workarounds
Disable IPv6 Router Advertisements
linuxPrevent processing of ICMPv6 router advertisements to block the attack vector
sysctl -w net.ipv6.conf.all.accept_ra=0
sysctl -w net.ipv6.conf.default.accept_ra=0
Disable IPv6 Entirely
linuxCompletely disable IPv6 if not needed
sysctl -w net.ipv6.conf.all.disable_ipv6=1
sysctl -w net.ipv6.conf.default.disable_ipv6=1
🧯 If You Can't Patch
- Implement strict network segmentation to limit adjacent network access
- Deploy network-based intrusion prevention systems to block malicious ICMPv6 packets
🔍 How to Verify
Check if Vulnerable:
Check kernel version and compare against patched versions for your distribution. For RHEL: 'uname -r' and check if version is before kernel-5.14.0-427.13.1.el9_4Check Version:
uname -rVerify Fix Applied:
Verify kernel version includes the fix commit: 'uname -r' should show patched version. Check sysctl settings if using workarounds: 'sysctl net.ipv6.conf.all.accept_ra' should return 0📡 Detection & Monitoring
Log Indicators:
- Kernel panic logs
- Unexpected process crashes
- System instability logs
Network Indicators:
- Unusual ICMPv6 router advertisement traffic from internal sources
- Suspicious network scanning on IPv6
SIEM Query:
source="kernel" AND ("panic" OR "oops" OR "segfault") OR protocol="ICMPv6" AND type="134" AND src_ip IN (internal_range)🔗 References
- https://access.redhat.com/security/cve/CVE-2023-6200
- https://bugzilla.redhat.com/show_bug.cgi?id=2250377
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=dade3f6a1e4e
- https://access.redhat.com/security/cve/CVE-2023-6200
- https://bugzilla.redhat.com/show_bug.cgi?id=2250377
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=dade3f6a1e4e
