{"api_version":"1","generated_at":"2026-05-11T11:04:34+00:00","cve":"CVE-2026-43456","urls":{"html":"https://cve.report/CVE-2026-43456","api":"https://cve.report/api/cve/CVE-2026-43456.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-43456","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-43456"},"summary":{"title":"bonding: fix type confusion in bond_setup_by_slave()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nbonding: fix type confusion in bond_setup_by_slave()\n\nkernel BUG at net/core/skbuff.c:2306!\nOops: invalid opcode: 0000 [#1] SMP KASAN NOPTI\nRIP: 0010:pskb_expand_head+0xa08/0xfe0 net/core/skbuff.c:2306\nRSP: 0018:ffffc90004aff760 EFLAGS: 00010293\nRAX: 0000000000000000 RBX: ffff88807e3c8780 RCX: ffffffff89593e0e\nRDX: ffff88807b7c4900 RSI: ffffffff89594747 RDI: ffff88807b7c4900\nRBP: 0000000000000820 R08: 0000000000000005 R09: 0000000000000000\nR10: 00000000961a63e0 R11: 0000000000000000 R12: ffff88807e3c8780\nR13: 00000000961a6560 R14: dffffc0000000000 R15: 00000000961a63e0\nCS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 00007fe1a0ed8df0 CR3: 000000002d816000 CR4: 00000000003526f0\nCall Trace:\n <TASK>\n ipgre_header+0xdd/0x540 net/ipv4/ip_gre.c:900\n dev_hard_header include/linux/netdevice.h:3439 [inline]\n packet_snd net/packet/af_packet.c:3028 [inline]\n packet_sendmsg+0x3ae5/0x53c0 net/packet/af_packet.c:3108\n sock_sendmsg_nosec net/socket.c:727 [inline]\n __sock_sendmsg net/socket.c:742 [inline]\n ____sys_sendmsg+0xa54/0xc30 net/socket.c:2592\n ___sys_sendmsg+0x190/0x1e0 net/socket.c:2646\n __sys_sendmsg+0x170/0x220 net/socket.c:2678\n do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]\n do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94\n entry_SYSCALL_64_after_hwframe+0x77/0x7f\nRIP: 0033:0x7fe1a0e6c1a9\n\nWhen a non-Ethernet device (e.g. GRE tunnel) is enslaved to a bond,\nbond_setup_by_slave() directly copies the slave's header_ops to the\nbond device:\n\n    bond_dev->header_ops = slave_dev->header_ops;\n\nThis causes a type confusion when dev_hard_header() is later called\non the bond device. Functions like ipgre_header(), ip6gre_header(),all use\nnetdev_priv(dev) to access their device-specific private data. When\ncalled with the bond device, netdev_priv() returns the bond's private\ndata (struct bonding) instead of the expected type (e.g. struct\nip_tunnel), leading to garbage values being read and kernel crashes.\n\nFix this by introducing bond_header_ops with wrapper functions that\ndelegate to the active slave's header_ops using the slave's own\ndevice. This ensures netdev_priv() in the slave's header functions\nalways receives the correct device.\n\nThe fix is placed in the bonding driver rather than individual device\ndrivers, as the root cause is bond blindly inheriting header_ops from\nthe slave without considering that these callbacks expect a specific\nnetdev_priv() layout.\n\nThe type confusion can be observed by adding a printk in\nipgre_header() and running the following commands:\n\n    ip link add dummy0 type dummy\n    ip addr add 10.0.0.1/24 dev dummy0\n    ip link set dummy0 up\n    ip link add gre1 type gre local 10.0.0.1\n    ip link add bond1 type bond mode active-backup\n    ip link set gre1 master bond1\n    ip link set gre1 up\n    ip link set bond1 up\n    ip addr add fe80::1/64 dev bond1","state":"PUBLISHED","assigner":"Linux","published_at":"2026-05-08 15:16:58","updated_at":"2026-05-11 08:16:14"},"problem_types":[],"metrics":[{"version":"3.1","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","score":"7.8","severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"}},{"version":"3.1","source":"CNA","type":"DECLARED","score":"7.8","severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","data":{"baseScore":7.8,"baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","version":"3.1"}}],"references":[{"url":"https://git.kernel.org/stable/c/6ac890f1d60ac3707ee8dae15a67d9a833e49956","name":"https://git.kernel.org/stable/c/6ac890f1d60ac3707ee8dae15a67d9a833e49956","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/9baf26a91565b7bb2b1d9f99aaf884a2b28c2f6d","name":"https://git.kernel.org/stable/c/9baf26a91565b7bb2b1d9f99aaf884a2b28c2f6d","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/950803f7254721c1c15858fbbfae3deaaeeecb11","name":"https://git.kernel.org/stable/c/950803f7254721c1c15858fbbfae3deaaeeecb11","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/95597d11dc8bddb2b9a051c9232000bfbb5e43ba","name":"https://git.kernel.org/stable/c/95597d11dc8bddb2b9a051c9232000bfbb5e43ba","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-43456","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-43456","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 1284cd3a2b740d0118458d2ea470a1e5bc19b187 9baf26a91565b7bb2b1d9f99aaf884a2b28c2f6d git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 1284cd3a2b740d0118458d2ea470a1e5bc19b187 6ac890f1d60ac3707ee8dae15a67d9a833e49956 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 1284cd3a2b740d0118458d2ea470a1e5bc19b187 95597d11dc8bddb2b9a051c9232000bfbb5e43ba git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 1284cd3a2b740d0118458d2ea470a1e5bc19b187 950803f7254721c1c15858fbbfae3deaaeeecb11 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 2.6.24","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 2.6.24 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.78 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.19 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.19.9 6.19.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.0 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"43456","cve":"CVE-2026-43456","epss":"0.000180000","percentile":"0.047390000","score_date":"2026-05-10","updated_at":"2026-05-11 00:14:41"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["drivers/net/bonding/bond_main.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"9baf26a91565b7bb2b1d9f99aaf884a2b28c2f6d","status":"affected","version":"1284cd3a2b740d0118458d2ea470a1e5bc19b187","versionType":"git"},{"lessThan":"6ac890f1d60ac3707ee8dae15a67d9a833e49956","status":"affected","version":"1284cd3a2b740d0118458d2ea470a1e5bc19b187","versionType":"git"},{"lessThan":"95597d11dc8bddb2b9a051c9232000bfbb5e43ba","status":"affected","version":"1284cd3a2b740d0118458d2ea470a1e5bc19b187","versionType":"git"},{"lessThan":"950803f7254721c1c15858fbbfae3deaaeeecb11","status":"affected","version":"1284cd3a2b740d0118458d2ea470a1e5bc19b187","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["drivers/net/bonding/bond_main.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"2.6.24"},{"lessThan":"2.6.24","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.78","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.19","versionType":"semver"},{"lessThanOrEqual":"6.19.*","status":"unaffected","version":"6.19.9","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.0","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.78","versionStartIncluding":"2.6.24","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.19","versionStartIncluding":"2.6.24","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.19.9","versionStartIncluding":"2.6.24","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.0","versionStartIncluding":"2.6.24","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nbonding: fix type confusion in bond_setup_by_slave()\n\nkernel BUG at net/core/skbuff.c:2306!\nOops: invalid opcode: 0000 [#1] SMP KASAN NOPTI\nRIP: 0010:pskb_expand_head+0xa08/0xfe0 net/core/skbuff.c:2306\nRSP: 0018:ffffc90004aff760 EFLAGS: 00010293\nRAX: 0000000000000000 RBX: ffff88807e3c8780 RCX: ffffffff89593e0e\nRDX: ffff88807b7c4900 RSI: ffffffff89594747 RDI: ffff88807b7c4900\nRBP: 0000000000000820 R08: 0000000000000005 R09: 0000000000000000\nR10: 00000000961a63e0 R11: 0000000000000000 R12: ffff88807e3c8780\nR13: 00000000961a6560 R14: dffffc0000000000 R15: 00000000961a63e0\nCS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 00007fe1a0ed8df0 CR3: 000000002d816000 CR4: 00000000003526f0\nCall Trace:\n <TASK>\n ipgre_header+0xdd/0x540 net/ipv4/ip_gre.c:900\n dev_hard_header include/linux/netdevice.h:3439 [inline]\n packet_snd net/packet/af_packet.c:3028 [inline]\n packet_sendmsg+0x3ae5/0x53c0 net/packet/af_packet.c:3108\n sock_sendmsg_nosec net/socket.c:727 [inline]\n __sock_sendmsg net/socket.c:742 [inline]\n ____sys_sendmsg+0xa54/0xc30 net/socket.c:2592\n ___sys_sendmsg+0x190/0x1e0 net/socket.c:2646\n __sys_sendmsg+0x170/0x220 net/socket.c:2678\n do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]\n do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94\n entry_SYSCALL_64_after_hwframe+0x77/0x7f\nRIP: 0033:0x7fe1a0e6c1a9\n\nWhen a non-Ethernet device (e.g. GRE tunnel) is enslaved to a bond,\nbond_setup_by_slave() directly copies the slave's header_ops to the\nbond device:\n\n    bond_dev->header_ops = slave_dev->header_ops;\n\nThis causes a type confusion when dev_hard_header() is later called\non the bond device. Functions like ipgre_header(), ip6gre_header(),all use\nnetdev_priv(dev) to access their device-specific private data. When\ncalled with the bond device, netdev_priv() returns the bond's private\ndata (struct bonding) instead of the expected type (e.g. struct\nip_tunnel), leading to garbage values being read and kernel crashes.\n\nFix this by introducing bond_header_ops with wrapper functions that\ndelegate to the active slave's header_ops using the slave's own\ndevice. This ensures netdev_priv() in the slave's header functions\nalways receives the correct device.\n\nThe fix is placed in the bonding driver rather than individual device\ndrivers, as the root cause is bond blindly inheriting header_ops from\nthe slave without considering that these callbacks expect a specific\nnetdev_priv() layout.\n\nThe type confusion can be observed by adding a printk in\nipgre_header() and running the following commands:\n\n    ip link add dummy0 type dummy\n    ip addr add 10.0.0.1/24 dev dummy0\n    ip link set dummy0 up\n    ip link add gre1 type gre local 10.0.0.1\n    ip link add bond1 type bond mode active-backup\n    ip link set gre1 master bond1\n    ip link set gre1 up\n    ip link set bond1 up\n    ip addr add fe80::1/64 dev bond1"}],"metrics":[{"cvssV3_1":{"baseScore":7.8,"baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","version":"3.1"}}],"providerMetadata":{"dateUpdated":"2026-05-11T06:34:42.762Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/9baf26a91565b7bb2b1d9f99aaf884a2b28c2f6d"},{"url":"https://git.kernel.org/stable/c/6ac890f1d60ac3707ee8dae15a67d9a833e49956"},{"url":"https://git.kernel.org/stable/c/95597d11dc8bddb2b9a051c9232000bfbb5e43ba"},{"url":"https://git.kernel.org/stable/c/950803f7254721c1c15858fbbfae3deaaeeecb11"}],"title":"bonding: fix type confusion in bond_setup_by_slave()","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-43456","datePublished":"2026-05-08T14:22:20.036Z","dateReserved":"2026-05-01T14:12:56.010Z","dateUpdated":"2026-05-11T06:34:42.762Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-05-08 15:16:58","lastModifiedDate":"2026-05-11 08:16:14","problem_types":[],"metrics":{"cvssMetricV31":[{"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"},"exploitabilityScore":1.8,"impactScore":5.9}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"43456","Ordinal":"1","Title":"bonding: fix type confusion in bond_setup_by_slave()","CVE":"CVE-2026-43456","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"43456","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nbonding: fix type confusion in bond_setup_by_slave()\n\nkernel BUG at net/core/skbuff.c:2306!\nOops: invalid opcode: 0000 [#1] SMP KASAN NOPTI\nRIP: 0010:pskb_expand_head+0xa08/0xfe0 net/core/skbuff.c:2306\nRSP: 0018:ffffc90004aff760 EFLAGS: 00010293\nRAX: 0000000000000000 RBX: ffff88807e3c8780 RCX: ffffffff89593e0e\nRDX: ffff88807b7c4900 RSI: ffffffff89594747 RDI: ffff88807b7c4900\nRBP: 0000000000000820 R08: 0000000000000005 R09: 0000000000000000\nR10: 00000000961a63e0 R11: 0000000000000000 R12: ffff88807e3c8780\nR13: 00000000961a6560 R14: dffffc0000000000 R15: 00000000961a63e0\nCS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 00007fe1a0ed8df0 CR3: 000000002d816000 CR4: 00000000003526f0\nCall Trace:\n <TASK>\n ipgre_header+0xdd/0x540 net/ipv4/ip_gre.c:900\n dev_hard_header include/linux/netdevice.h:3439 [inline]\n packet_snd net/packet/af_packet.c:3028 [inline]\n packet_sendmsg+0x3ae5/0x53c0 net/packet/af_packet.c:3108\n sock_sendmsg_nosec net/socket.c:727 [inline]\n __sock_sendmsg net/socket.c:742 [inline]\n ____sys_sendmsg+0xa54/0xc30 net/socket.c:2592\n ___sys_sendmsg+0x190/0x1e0 net/socket.c:2646\n __sys_sendmsg+0x170/0x220 net/socket.c:2678\n do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]\n do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94\n entry_SYSCALL_64_after_hwframe+0x77/0x7f\nRIP: 0033:0x7fe1a0e6c1a9\n\nWhen a non-Ethernet device (e.g. GRE tunnel) is enslaved to a bond,\nbond_setup_by_slave() directly copies the slave's header_ops to the\nbond device:\n\n    bond_dev->header_ops = slave_dev->header_ops;\n\nThis causes a type confusion when dev_hard_header() is later called\non the bond device. Functions like ipgre_header(), ip6gre_header(),all use\nnetdev_priv(dev) to access their device-specific private data. When\ncalled with the bond device, netdev_priv() returns the bond's private\ndata (struct bonding) instead of the expected type (e.g. struct\nip_tunnel), leading to garbage values being read and kernel crashes.\n\nFix this by introducing bond_header_ops with wrapper functions that\ndelegate to the active slave's header_ops using the slave's own\ndevice. This ensures netdev_priv() in the slave's header functions\nalways receives the correct device.\n\nThe fix is placed in the bonding driver rather than individual device\ndrivers, as the root cause is bond blindly inheriting header_ops from\nthe slave without considering that these callbacks expect a specific\nnetdev_priv() layout.\n\nThe type confusion can be observed by adding a printk in\nipgre_header() and running the following commands:\n\n    ip link add dummy0 type dummy\n    ip addr add 10.0.0.1/24 dev dummy0\n    ip link set dummy0 up\n    ip link add gre1 type gre local 10.0.0.1\n    ip link add bond1 type bond mode active-backup\n    ip link set gre1 master bond1\n    ip link set gre1 up\n    ip link set bond1 up\n    ip addr add fe80::1/64 dev bond1","Type":"Description","Title":"bonding: fix type confusion in bond_setup_by_slave()"}]}}}