CVE-2026-23171 – A use-after-free vulnerability in the Linux ker... (How to Fix)

Q: What is the severity of CVE-2026-23171?

CVE-2026-23171 has a CVSS score of N/A (Unknown). A use-after-free vulnerability in the Linux kernel bonding driver allows attackers to cause a kernel crash or potentially execute arbitrary code. This affects systems using network bonding with XDP programs when slave addition fails. The vulnerability can be triggered by unprivileged users who can add network interfaces to bonds.

📋 TL;DR

A use-after-free vulnerability in the Linux kernel bonding driver allows attackers to cause a kernel crash or potentially execute arbitrary code. This affects systems using network bonding with XDP programs when slave addition fails. The vulnerability can be triggered by unprivileged users who can add network interfaces to bonds.

💻 Affected Systems

Products:

Linux kernel

Versions: Kernel versions before the fix commit bd25b092a06a3e05f7e8bd6da6fa7318777d8c3d (likely 6.19.0-rc6 and earlier)

Operating Systems: Linux distributions using affected kernel versions

Default Config Vulnerable: ✅ No

Notes: Only vulnerable when using network bonding with XDP programs and experiencing slave addition failures. Requires CONFIG_BONDING=y and XDP support.

⚠️ Manual Verification Required

This CVE does not have specific version information in our database, so automatic vulnerability detection cannot determine if your system is affected.

Why? The CVE database entry doesn't specify which versions are vulnerable (no version ranges provided by the vendor/NVD).

🔒 Custom verification scripts are available for registered users. Sign up free to download automated test scripts.

Recommended Actions:

Review the CVE details at NVD
Check vendor security advisories for your specific version
Test if the vulnerability is exploitable in your environment
Consider updating to the latest version as a precaution

⚠️ Risk & Real-World Impact

🔴

Worst Case

Kernel panic leading to system crash, or potential arbitrary code execution with kernel privileges resulting in complete system compromise.

🟠

Likely Case

System crash or kernel panic causing denial of service, requiring system reboot to restore functionality.

🟢

If Mitigated

No impact if bonding is not used, XDP programs are not loaded, or the system is patched.

🌐 Internet-Facing: MEDIUM - Requires network access and ability to send packets to trigger the condition, but exploitation requires specific timing and configuration.

🏢 Internal Only: MEDIUM - Internal attackers with network access could crash systems using vulnerable bonding configurations.

🎯 Exploit Status

Public PoC: ✅ No

Weaponized: UNKNOWN

Unauthenticated Exploit: ✅ No

Complexity: MEDIUM

Exploitation requires specific timing conditions and network bonding configuration. The provided reproduction steps demonstrate how to trigger the crash.

🛠️ Fix & Mitigation

✅ Official Fix

Patch Version: Kernel versions including commit bd25b092a06a3e05f7e8bd6da6fa7318777d8c3d

Vendor Advisory: https://git.kernel.org/stable/c/bd25b092a06a3e05f7e8bd6da6fa7318777d8c3d

Restart Required: Yes

Instructions:

1. Update Linux kernel to version containing the fix commit. 2. For distributions: Use package manager to install latest kernel updates. 3. Reboot system to load new kernel.

🔧 Temporary Workarounds

Disable bonding or XDP

all

Remove XDP programs from bond interfaces or disable bonding entirely if not required

ip link set dev bond1 xdp off
ip link del bond1

Restrict interface management

all

Prevent unauthorized users from adding interfaces to bonds using capabilities or network namespaces

setcap -r /sbin/ip
Use network namespaces with restricted privileges

🧯 If You Can't Patch

Disable network bonding feature if not required (remove bonding kernel module)
Implement strict network segmentation to limit who can send packets to bond interfaces

🔍 How to Verify

Check if Vulnerable:

Check kernel version and if bonding with XDP is configured: uname -r && ip link show type bond && ip link show | grep -A5 xdp

Check Version:

uname -r

Verify Fix Applied:

Verify kernel version includes fix commit: grep -q bd25b092a06a3e05f7e8bd6da6fa7318777d8c3d /proc/version_signature || echo 'Check kernel changelog'

📡 Detection & Monitoring

Log Indicators:

Kernel panic messages mentioning bonding, use-after-free, or general protection fault in netdev_core_pick_tx

Network Indicators:

Unusual packet patterns to bond interfaces with rapid slave addition/removal

SIEM Query:

source="kernel" AND ("bonding" OR "use-after-free" OR "general protection fault")

📊 Metadata

CVE ID: CVE-2026-23171

CVSS v3 Score: N/A (Unknown)

Published: February 14, 2026

Last Updated: February 18, 2026

🔗 References

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