CVE-2023-54206

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2023-54206", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-12-30T12:06:44.499Z", "datePublished": "2025-12-30T12:11:05.945Z", "dateUpdated": "2026-10-15T21:41:41.534Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T09:18:03.513Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: flower: fix filter idr initialization\n\nThe cited commit moved idr initialization too early in fl_change() which\nallows concurrent users to access the filter that is still being\ninitialized and is in inconsistent state, which, in turn, can cause NULL\npointer dereference [0]. Since there is no obvious way to fix the ordering\nwithout reverting the whole cited commit, alternative approach taken to\nfirst insert NULL pointer into idr in order to allocate the handle but\nstill cause fl_get() to return NULL and prevent concurrent users from\nseeing the filter while providing miss-to-action infrastructure with valid\nhandle id early in fl_change().\n\n[ 152.434728] general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN\n[ 152.436163] KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]\n[ 152.437269] CPU: 4 PID: 3877 Comm: tc Not tainted 6.3.0-rc4+ #5\n[ 152.438110] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014\n[ 152.439644] RIP: 0010:fl_dump_key+0x8b/0x1d10 [cls_flower]\n[ 152.440461] Code: 01 f2 02 f2 c7 40 08 04 f2 04 f2 c7 40 0c 04 f3 f3 f3 65 48 8b 04 25 28 00 00 00 48 89 84 24 00 01 00 00 48 89 c8 48 c1 e8 03 <0f> b6 04 10 84 c0 74 08 3c 03 0f 8e 98 19 00 00 8b 13 85 d2 74 57\n[ 152.442885] RSP: 0018:ffff88817a28f158 EFLAGS: 00010246\n[ 152.443851] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000\n[ 152.444826] RDX: dffffc0000000000 RSI: ffffffff8500ae80 RDI: ffff88810a987900\n[ 152.445791] RBP: ffff888179d88240 R08: ffff888179d8845c R09: ffff888179d88240\n[ 152.446780] R10: ffffed102f451e48 R11: 00000000fffffff2 R12: ffff88810a987900\n[ 152.447741] R13: ffffffff8500ae80 R14: ffff88810a987900 R15: ffff888149b3c738\n[ 152.448756] FS: 00007f5eb2a34800(0000) GS:ffff88881ec00000(0000) knlGS:0000000000000000\n[ 152.449888] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n[ 152.450685] CR2: 000000000046ad19 CR3: 000000010b0bd006 CR4: 0000000000370ea0\n[ 152.451641] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\n[ 152.452628] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400\n[ 152.453588] Call Trace:\n[ 152.454032] <TASK>\n[ 152.454447] ? netlink_sendmsg+0x7a1/0xcb0\n[ 152.455109] ? sock_sendmsg+0xc5/0x190\n[ 152.455689] ? ____sys_sendmsg+0x535/0x6b0\n[ 152.456320] ? ___sys_sendmsg+0xeb/0x170\n[ 152.456916] ? do_syscall_64+0x3d/0x90\n[ 152.457529] ? entry_SYSCALL_64_after_hwframe+0x46/0xb0\n[ 152.458321] ? ___sys_sendmsg+0xeb/0x170\n[ 152.458958] ? __sys_sendmsg+0xb5/0x140\n[ 152.459564] ? do_syscall_64+0x3d/0x90\n[ 152.460122] ? entry_SYSCALL_64_after_hwframe+0x46/0xb0\n[ 152.460852] ? fl_dump_key_options.part.0+0xea0/0xea0 [cls_flower]\n[ 152.461710] ? _raw_spin_lock+0x7a/0xd0\n[ 152.462299] ? _raw_read_lock_irq+0x30/0x30\n[ 152.462924] ? nla_put+0x15e/0x1c0\n[ 152.463480] fl_dump+0x228/0x650 [cls_flower]\n[ 152.464112] ? fl_tmplt_dump+0x210/0x210 [cls_flower]\n[ 152.464854] ? __kmem_cache_alloc_node+0x1a7/0x330\n[ 152.465592] ? nla_put+0x15e/0x1c0\n[ 152.466160] tcf_fill_node+0x515/0x9a0\n[ 152.466766] ? tc_setup_offload_action+0xf0/0xf0\n[ 152.467463] ? __alloc_skb+0x13c/0x2a0\n[ 152.468067] ? __build_skb_around+0x330/0x330\n[ 152.468814] ? fl_get+0x107/0x1a0 [cls_flower]\n[ 152.469503] tc_del_tfilter+0x718/0x1330\n[ 152.470115] ? is_bpf_text_address+0xa/0x20\n[ 152.470765] ? tc_ctl_chain+0xee0/0xee0\n[ 152.471335] ? __kernel_text_address+0xe/0x30\n[ 152.471948] ? unwind_get_return_address+0x56/0xa0\n[ 152.472639] ? __thaw_task+0x150/0x150\n[ 152.473218] ? arch_stack_walk+0x98/0xf0\n[ 152.473839] ? __stack_depot_save+0x35/0x4c0\n[ 152.474501] ? stack_trace_save+0x91/0xc0\n[ 152.475119] ? security_capable+0x51/0x90\n[ 152.475741] rtnetlink_rcv_msg+0x2c1/0x9d0\n[ 152.476387] ? rtnl_calcit.isra.0+0x2b0/0x2b0\n[ 152.477042]\n---truncated---"}], "metrics": [{"cvssV3_1": {"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"}, "scenarios": [{"lang": "en", "value": "AV:L - The vulnerability is reached exclusively through RTM_NEWTFILTER/RTM_GETTFILTER/RTM_DELTFILTER rtnetlink messages sent on a local netlink socket (tc filter add/get/del on a clsact/ingress qdisc). There is no remote packet-processing path into fl_change()/fl_get().\nAC:L - The attacker controls both sides of the race, running one thread that issues a filter add with a chosen handle and another that gets/deletes/dumps that same handle; cls_flower is TCF_PROTO_OPS_DOIT_UNLOCKED so the two run concurrently without RTNL serialization. The window spans netlink parsing, action validation, sleeping GFP_KERNEL allocations and hardware offload callbacks, and can be widened at will with expensive action lists \u2014 the original reporter hit it with ordinary tc commands.\nPR:L - tc filter operations are gated by netlink_net_capable(CAP_NET_ADMIN), which is evaluated against the netns owner's user namespace, so an unprivileged local user obtains it via `unshare -Urn` and then creates a dummy device, a clsact qdisc and flower filters. No real root in the initial namespace is required.\nUI:N - The attacker performs both the filter-add and the concurrent get/delete/dump itself from its own processes. No action by any other user or administrator is needed.\nS:U - The corruption is confined to kernel memory managed by the same kernel security authority that the attacker is already interacting with; there is no VM, IOMMU, or sandbox boundary crossed.\nC:H - A concurrent reader obtains a reference to a filter in an inconsistent state, and __fl_delete()/fl_mask_put() can tear down and free the fl_flow_mask while the initializing thread still dereferences f->mask in fl_hw_replace_filter(), plus idr_remove/idr_replace desync allows a handle to be re-pointed at another filter \u2014 use-after-free style corruption of this class is leveragable for kernel memory disclosure.\nI:H - The race yields writes through uninitialized/stale state \u2014 list_del_rcu() on a zeroed list_head, list_add_tail_rcu() onto a mask that a concurrent deleter may already have released, and idr entries desynchronized from the filter lists \u2014 which is heap corruption exploitable for control-flow hijack, not merely a benign inconsistency.\nA:H - The demonstrated outcome is a NULL pointer dereference/general protection fault in fl_dump_key() that occurs while tp->lock is held, so the oops both kills the task and leaves the tcf_proto spinlock permanently held, deadlocking every subsequent filter operation on that block. Either the crash alone or the resulting hang is a full availability loss, and it can be retriggered at will."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/sched/cls_flower.c"], "versions": [{"version": "08a0063df3aed8d76a4034279117db12dbc1050f", "lessThan": "253a3a324e0ebc2825de76a0f5f17b8383b2023d", "status": "affected", "versionType": "git"}, {"version": "08a0063df3aed8d76a4034279117db12dbc1050f", "lessThan": "dd4f6bbfa646f258e5bcdfac57a5c413d687f588", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/sched/cls_flower.c"], "versions": [{"version": "6.3", "status": "affected"}, {"version": "0", "lessThan": "6.3", "status": "unaffected", "versionType": "semver"}, {"version": "6.3.3", "lessThanOrEqual": "6.3.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.4", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.3", "versionEndExcluding": "6.3.3"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.3", "versionEndExcluding": "6.4"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/253a3a324e0ebc2825de76a0f5f17b8383b2023d"}, {"url": "https://git.kernel.org/stable/c/dd4f6bbfa646f258e5bcdfac57a5c413d687f588"}], "title": "net/sched: flower: fix filter idr initialization", "x_generator": {"engine": "bippy-1.2.0"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2023-54206", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "total"}], "version": "2.0.3", "timestamp": "2026-10-15T21:39:20.326820Z"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-15T21:41:41.534Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2023-54206", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "total"}], "version": "2.0.3", "timestamp": "2026-10-15T21:39:20.326820Z"}}}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-15T21:39:20.805Z"}}], "cna": {"title": "net/sched: flower: fix filter idr initialization", "metrics": [{"cvssV3_1": {"version": "3.1", "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"}, "scenarios": [{"lang": "en", "value": "AV:L - The vulnerability is reached exclusively through RTM_NEWTFILTER/RTM_GETTFILTER/RTM_DELTFILTER rtnetlink messages sent on a local netlink socket (tc filter add/get/del on a clsact/ingress qdisc). There is no remote packet-processing path into fl_change()/fl_get().\nAC:L - The attacker controls both sides of the race, running one thread that issues a filter add with a chosen handle and another that gets/deletes/dumps that same handle; cls_flower is TCF_PROTO_OPS_DOIT_UNLOCKED so the two run concurrently without RTNL serialization. The window spans netlink parsing, action validation, sleeping GFP_KERNEL allocations and hardware offload callbacks, and can be widened at will with expensive action lists \u2014 the original reporter hit it with ordinary tc commands.\nPR:L - tc filter operations are gated by netlink_net_capable(CAP_NET_ADMIN), which is evaluated against the netns owner's user namespace, so an unprivileged local user obtains it via `unshare -Urn` and then creates a dummy device, a clsact qdisc and flower filters. No real root in the initial namespace is required.\nUI:N - The attacker performs both the filter-add and the concurrent get/delete/dump itself from its own processes. No action by any other user or administrator is needed.\nS:U - The corruption is confined to kernel memory managed by the same kernel security authority that the attacker is already interacting with; there is no VM, IOMMU, or sandbox boundary crossed.\nC:H - A concurrent reader obtains a reference to a filter in an inconsistent state, and __fl_delete()/fl_mask_put() can tear down and free the fl_flow_mask while the initializing thread still dereferences f->mask in fl_hw_replace_filter(), plus idr_remove/idr_replace desync allows a handle to be re-pointed at another filter \u2014 use-after-free style corruption of this class is leveragable for kernel memory disclosure.\nI:H - The race yields writes through uninitialized/stale state \u2014 list_del_rcu() on a zeroed list_head, list_add_tail_rcu() onto a mask that a concurrent deleter may already have released, and idr entries desynchronized from the filter lists \u2014 which is heap corruption exploitable for control-flow hijack, not merely a benign inconsistency.\nA:H - The demonstrated outcome is a NULL pointer dereference/general protection fault in fl_dump_key() that occurs while tp->lock is held, so the oops both kills the task and leaves the tcf_proto spinlock permanently held, deadlocking every subsequent filter operation on that block. Either the crash alone or the resulting hang is a full availability loss, and it can be retriggered at will."}]}], "affected": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "08a0063df3aed8d76a4034279117db12dbc1050f", "lessThan": "253a3a324e0ebc2825de76a0f5f17b8383b2023d", "versionType": "git"}, {"status": "affected", "version": "08a0063df3aed8d76a4034279117db12dbc1050f", "lessThan": "dd4f6bbfa646f258e5bcdfac57a5c413d687f588", "versionType": "git"}], "programFiles": ["net/sched/cls_flower.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "6.3"}, {"status": "unaffected", "version": "0", "lessThan": "6.3", "versionType": "semver"}, {"status": "unaffected", "version": "6.3.3", "versionType": "semver", "lessThanOrEqual": "6.3.*"}, {"status": "unaffected", "version": "6.4", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["net/sched/cls_flower.c"], "defaultStatus": "affected"}], "references": [{"url": "https://git.kernel.org/stable/c/253a3a324e0ebc2825de76a0f5f17b8383b2023d"}, {"url": "https://git.kernel.org/stable/c/dd4f6bbfa646f258e5bcdfac57a5c413d687f588"}], "x_generator": {"engine": "bippy-1.2.0"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: flower: fix filter idr initialization\n\nThe cited commit moved idr initialization too early in fl_change() which\nallows concurrent users to access the filter that is still being\ninitialized and is in inconsistent state, which, in turn, can cause NULL\npointer dereference [0]. Since there is no obvious way to fix the ordering\nwithout reverting the whole cited commit, alternative approach taken to\nfirst insert NULL pointer into idr in order to allocate the handle but\nstill cause fl_get() to return NULL and prevent concurrent users from\nseeing the filter while providing miss-to-action infrastructure with valid\nhandle id early in fl_change().\n\n[ 152.434728] general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN\n[ 152.436163] KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]\n[ 152.437269] CPU: 4 PID: 3877 Comm: tc Not tainted 6.3.0-rc4+ #5\n[ 152.438110] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014\n[ 152.439644] RIP: 0010:fl_dump_key+0x8b/0x1d10 [cls_flower]\n[ 152.440461] Code: 01 f2 02 f2 c7 40 08 04 f2 04 f2 c7 40 0c 04 f3 f3 f3 65 48 8b 04 25 28 00 00 00 48 89 84 24 00 01 00 00 48 89 c8 48 c1 e8 03 <0f> b6 04 10 84 c0 74 08 3c 03 0f 8e 98 19 00 00 8b 13 85 d2 74 57\n[ 152.442885] RSP: 0018:ffff88817a28f158 EFLAGS: 00010246\n[ 152.443851] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000\n[ 152.444826] RDX: dffffc0000000000 RSI: ffffffff8500ae80 RDI: ffff88810a987900\n[ 152.445791] RBP: ffff888179d88240 R08: ffff888179d8845c R09: ffff888179d88240\n[ 152.446780] R10: ffffed102f451e48 R11: 00000000fffffff2 R12: ffff88810a987900\n[ 152.447741] R13: ffffffff8500ae80 R14: ffff88810a987900 R15: ffff888149b3c738\n[ 152.448756] FS: 00007f5eb2a34800(0000) GS:ffff88881ec00000(0000) knlGS:0000000000000000\n[ 152.449888] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n[ 152.450685] CR2: 000000000046ad19 CR3: 000000010b0bd006 CR4: 0000000000370ea0\n[ 152.451641] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\n[ 152.452628] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400\n[ 152.453588] Call Trace:\n[ 152.454032] <TASK>\n[ 152.454447] ? netlink_sendmsg+0x7a1/0xcb0\n[ 152.455109] ? sock_sendmsg+0xc5/0x190\n[ 152.455689] ? ____sys_sendmsg+0x535/0x6b0\n[ 152.456320] ? ___sys_sendmsg+0xeb/0x170\n[ 152.456916] ? do_syscall_64+0x3d/0x90\n[ 152.457529] ? entry_SYSCALL_64_after_hwframe+0x46/0xb0\n[ 152.458321] ? ___sys_sendmsg+0xeb/0x170\n[ 152.458958] ? __sys_sendmsg+0xb5/0x140\n[ 152.459564] ? do_syscall_64+0x3d/0x90\n[ 152.460122] ? entry_SYSCALL_64_after_hwframe+0x46/0xb0\n[ 152.460852] ? fl_dump_key_options.part.0+0xea0/0xea0 [cls_flower]\n[ 152.461710] ? _raw_spin_lock+0x7a/0xd0\n[ 152.462299] ? _raw_read_lock_irq+0x30/0x30\n[ 152.462924] ? nla_put+0x15e/0x1c0\n[ 152.463480] fl_dump+0x228/0x650 [cls_flower]\n[ 152.464112] ? fl_tmplt_dump+0x210/0x210 [cls_flower]\n[ 152.464854] ? __kmem_cache_alloc_node+0x1a7/0x330\n[ 152.465592] ? nla_put+0x15e/0x1c0\n[ 152.466160] tcf_fill_node+0x515/0x9a0\n[ 152.466766] ? tc_setup_offload_action+0xf0/0xf0\n[ 152.467463] ? __alloc_skb+0x13c/0x2a0\n[ 152.468067] ? __build_skb_around+0x330/0x330\n[ 152.468814] ? fl_get+0x107/0x1a0 [cls_flower]\n[ 152.469503] tc_del_tfilter+0x718/0x1330\n[ 152.470115] ? is_bpf_text_address+0xa/0x20\n[ 152.470765] ? tc_ctl_chain+0xee0/0xee0\n[ 152.471335] ? __kernel_text_address+0xe/0x30\n[ 152.471948] ? unwind_get_return_address+0x56/0xa0\n[ 152.472639] ? __thaw_task+0x150/0x150\n[ 152.473218] ? arch_stack_walk+0x98/0xf0\n[ 152.473839] ? __stack_depot_save+0x35/0x4c0\n[ 152.474501] ? stack_trace_save+0x91/0xc0\n[ 152.475119] ? security_capable+0x51/0x90\n[ 152.475741] rtnetlink_rcv_msg+0x2c1/0x9d0\n[ 152.476387] ? rtnl_calcit.isra.0+0x2b0/0x2b0\n[ 152.477042]\n---truncated---"}], "cpeApplicability": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.3.3", "versionStartIncluding": "6.3"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.4", "versionStartIncluding": "6.3"}], "operator": "OR"}]}], "providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T09:18:03.513Z"}}}, "cveMetadata": {"cveId": "CVE-2023-54206", "state": "PUBLISHED", "dateUpdated": "2026-10-15T21:41:41.534Z", "dateReserved": "2025-12-30T12:06:44.499Z", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "datePublished": "2025-12-30T12:11:05.945Z", "assignerShortName": "Linux"}, "dataVersion": "5.2"}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["net/sched/cls_flower.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "253a3a324e0ebc2825de76a0f5f17b8383b2023d", "status": "affected", "version": "08a0063df3aed8d76a4034279117db12dbc1050f", "versionType": "git"}, {"lessThan": "dd4f6bbfa646f258e5bcdfac57a5c413d687f588", "status": "affected", "version": "08a0063df3aed8d76a4034279117db12dbc1050f", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["net/sched/cls_flower.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "6.3"}, {"lessThan": "6.3", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.3.*", "status": "unaffected", "version": "6.3.3", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "6.4", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: flower: fix filter idr initialization\n\nThe cited commit moved idr initialization too early in fl_change() which\nallows concurrent users to access the filter that is still being\ninitialized and is in inconsistent state, which, in turn, can cause NULL\npointer dereference [0]. Since there is no obvious way to fix the ordering\nwithout reverting the whole cited commit, alternative approach taken to\nfirst insert NULL pointer into idr in order to allocate the handle but\nstill cause fl_get() to return NULL and prevent concurrent users from\nseeing the filter while providing miss-to-action infrastructure with valid\nhandle id early in fl_change().\n\n[ 152.434728] general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN\n[ 152.436163] KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]\n[ 152.437269] CPU: 4 PID: 3877 Comm: tc Not tainted 6.3.0-rc4+ #5\n[ 152.438110] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014\n[ 152.439644] RIP: 0010:fl_dump_key+0x8b/0x1d10 [cls_flower]\n[ 152.440461] Code: 01 f2 02 f2 c7 40 08 04 f2 04 f2 c7 40 0c 04 f3 f3 f3 65 48 8b 04 25 28 00 00 00 48 89 84 24 00 01 00 00 48 89 c8 48 c1 e8 03 <0f> b6 04 10 84 c0 74 08 3c 03 0f 8e 98 19 00 00 8b 13 85 d2 74 57\n[ 152.442885] RSP: 0018:ffff88817a28f158 EFLAGS: 00010246\n[ 152.443851] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000\n[ 152.444826] RDX: dffffc0000000000 RSI: ffffffff8500ae80 RDI: ffff88810a987900\n[ 152.445791] RBP: ffff888179d88240 R08: ffff888179d8845c R09: ffff888179d88240\n[ 152.446780] R10: ffffed102f451e48 R11: 00000000fffffff2 R12: ffff88810a987900\n[ 152.447741] R13: ffffffff8500ae80 R14: ffff88810a987900 R15: ffff888149b3c738\n[ 152.448756] FS: 00007f5eb2a34800(0000) GS:ffff88881ec00000(0000) knlGS:0000000000000000\n[ 152.449888] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n[ 152.450685] CR2: 000000000046ad19 CR3: 000000010b0bd006 CR4: 0000000000370ea0\n[ 152.451641] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\n[ 152.452628] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400\n[ 152.453588] Call Trace:\n[ 152.454032] <TASK>\n[ 152.454447] ? netlink_sendmsg+0x7a1/0xcb0\n[ 152.455109] ? sock_sendmsg+0xc5/0x190\n[ 152.455689] ? ____sys_sendmsg+0x535/0x6b0\n[ 152.456320] ? ___sys_sendmsg+0xeb/0x170\n[ 152.456916] ? do_syscall_64+0x3d/0x90\n[ 152.457529] ? entry_SYSCALL_64_after_hwframe+0x46/0xb0\n[ 152.458321] ? ___sys_sendmsg+0xeb/0x170\n[ 152.458958] ? __sys_sendmsg+0xb5/0x140\n[ 152.459564] ? do_syscall_64+0x3d/0x90\n[ 152.460122] ? entry_SYSCALL_64_after_hwframe+0x46/0xb0\n[ 152.460852] ? fl_dump_key_options.part.0+0xea0/0xea0 [cls_flower]\n[ 152.461710] ? _raw_spin_lock+0x7a/0xd0\n[ 152.462299] ? _raw_read_lock_irq+0x30/0x30\n[ 152.462924] ? nla_put+0x15e/0x1c0\n[ 152.463480] fl_dump+0x228/0x650 [cls_flower]\n[ 152.464112] ? fl_tmplt_dump+0x210/0x210 [cls_flower]\n[ 152.464854] ? __kmem_cache_alloc_node+0x1a7/0x330\n[ 152.465592] ? nla_put+0x15e/0x1c0\n[ 152.466160] tcf_fill_node+0x515/0x9a0\n[ 152.466766] ? tc_setup_offload_action+0xf0/0xf0\n[ 152.467463] ? __alloc_skb+0x13c/0x2a0\n[ 152.468067] ? __build_skb_around+0x330/0x330\n[ 152.468814] ? fl_get+0x107/0x1a0 [cls_flower]\n[ 152.469503] tc_del_tfilter+0x718/0x1330\n[ 152.470115] ? is_bpf_text_address+0xa/0x20\n[ 152.470765] ? tc_ctl_chain+0xee0/0xee0\n[ 152.471335] ? __kernel_text_address+0xe/0x30\n[ 152.471948] ? unwind_get_return_address+0x56/0xa0\n[ 152.472639] ? __thaw_task+0x150/0x150\n[ 152.473218] ? arch_stack_walk+0x98/0xf0\n[ 152.473839] ? __stack_depot_save+0x35/0x4c0\n[ 152.474501] ? stack_trace_save+0x91/0xc0\n[ 152.475119] ? security_capable+0x51/0x90\n[ 152.475741] rtnetlink_rcv_msg+0x2c1/0x9d0\n[ 152.476387] ? rtnl_calcit.isra.0+0x2b0/0x2b0\n[ 152.477042]\n---truncated---"}, {"lang": "es", "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nnet/sched: flower: correcci\u00f3n de la inicializaci\u00f3n del idr del filtro\n\nLa confirmaci\u00f3n citada movi\u00f3 la inicializaci\u00f3n del idr demasiado pronto en fl_change(), lo que permite a los usuarios concurrentes acceder al filtro que a\u00fan se est\u00e1 inicializando y se encuentra en un estado inconsistente, lo que, a su vez, puede causar una desreferencia de puntero NULL [0]. Dado que no hay una forma obvia de corregir el orden sin revertir la totalidad de la confirmaci\u00f3n citada, se adopt\u00f3 un enfoque alternativo para primero insertar un puntero NULL en el idr con el fin de asignar el identificador, pero a\u00fan as\u00ed hacer que fl_get() devuelva NULL y evitar que los usuarios concurrentes vean el filtro, mientras se proporciona a la infraestructura de acci\u00f3n por fallo un ID de identificador v\u00e1lido temprano en fl_change().\n\n[ 152.434728] fallo de protecci\u00f3n general, probablemente para una direcci\u00f3n no can\u00f3nica 0xdffffc0000000000: 0000 [#1] SMP KASAN\n[ 152.436163] KASAN: desreferencia de puntero nulo en el rango [0x0000000000000000-0x0000000000000007]\n[ 152.437269] CPU: 4 PID: 3877 Comm: tc No contaminado 6.3.0-rc4+ #5\n[ 152.438110] Nombre del hardware: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014\n[ 152.439644] RIP: 0010:fl_dump_key+0x8b/0x1d10 [cls_flower]\n[ 152.440461] Code: 01 f2 02 f2 c7 40 08 04 f2 04 f2 c7 40 0c 04 f3 f3 f3 65 48 8b 04 25 28 00 00 00 48 89 84 24 00 01 00 00 48 89 c8 48 c1 e8 03 [0f] b6 04 10 84 c0 74 08 3c 03 0f 8e 98 19 00 00 8b 13 85 d2 74 57\n[ 152.442885] RSP: 0018:ffff88817a28f158 EFLAGS: 00010246\n[ 152.443851] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000\n[ 152.444826] RDX: dffffc0000000000 RSI: ffffffff8500ae80 RDI: ffff88810a987900\n[ 152.445791] RBP: ffff888179d88240 R08: ffff888179d8845c R09: ffff888179d88240\n[ 152.446780] R10: ffffed102f451e48 R11: 00000000fffffff2 R12: ffff88810a987900\n[ 152.447741] R13: ffffffff8500ae80 R14: ffff88810a987900 R15: ffff888149b3c738\n[ 152.448756] FS: 00007f5eb2a34800(0000) GS:ffff88881ec00000(0000) knlGS:0000000000000000\n[ 152.449888] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n[ 152.450685] CR2: 000000000046ad19 CR3: 000000010b0bd006 CR4: 0000000000370ea0\n[ 152.451641] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\n[ 152.452628] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400\n[ 152.453588] Traza de llamadas:\n[ 152.454032] [TASK]\n[ 152.454447] ? netlink_sendmsg+0x7a1/0xcb0\n[ 152.455109] ? sock_sendmsg+0xc5/0x190\n[ 152.455689] ? ____sys_sendmsg+0x535/0x6b0\n[ 152.456320] ? ___sys_sendmsg+0xeb/0x170\n[ 152.456916] ? do_syscall_64+0x3d/0x90\n[ 152.457529] ? entry_SYSCALL_64_after_hwframe+0x46/0xb0\n[ 152.458321] ? ___sys_sendmsg+0xeb/0x170\n[ 152.458958] ? __sys_sendmsg+0xb5/0x140\n[ 152.459564] ? do_syscall_64+0x3d/0x90\n[ 152.460122] ? entry_SYSCALL_64_after_hwframe+0x46/0xb0\n[ 152.460852] ? fl_dump_key_options.part.0+0xea0/0xea0 [cls_flower]\n[ 152.461710] ? _raw_spin_lock+0x7a/0xd0\n[ 152.462299] ? _raw_read_lock_irq+0x30/0x30\n[ 152.462924] ? nla_put+0x15e/0x1c0\n[ 152.463480] fl_dump+0x228/0x650 [cls_flower]\n[ 152.464112] ? fl_tmplt_dump+0x210/0x210 [cls_flower]\n[ 152.464854] ? __kmem_cache_alloc_node+0x1a7/0x330\n[ 152.465592] ? nla_put+0x15e/0x1c0\n[ 152.466160] tcf_fill_node+0x515/0x9a0\n[ 152.466766] ? tc_setup_offload_action+0xf0/0xf0\n[ 152.467463] ? __alloc_skb+0x13c/0x2a0\n[ 152.468067] ? __build_skb_around+0x330/0x330\n[ 152.468814] ? fl_get+0x107/0x1a0 [cls_flower]\n[ 152.469503] tc_del_tfilter+0x718/0x1330\n[ 152.470115] ? is_bpf_text_address+0xa/0x20\n[ 152.470765] ? tc_ctl_chain+0xee0/0xee0\n[ 152.471335] ? __kernel_text_address+0xe/0x30\n[ 152.471948] ? unwind_get_return_address+0x56/0xa0\n[ 152.472639] ? __thaw_task+0x150/0x150\n[ 152.473218] ? arch_stack_walk+0x98/0xf0\n[ 152.473839] ? __stack_depot_save+0x35/0x4c0\n[ 152.474501] ? stack_trace_save+0x91/0xc0\n[ 152.475119] ? security_capable+0x51/0x90\n[ 152.475741] rtnetlink_rcv_msg+0x2c1/0x9d0\n[ 152.476387] ? --TRUNCADO--"}], "id": "CVE-2023-54206", "lastModified": "2026-10-28T19:10:00.193", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7.8, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 5.9, "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2023-54206", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "total"}], "role": "CISA Coordinator", "timestamp": "2026-10-15T21:39:20.326820Z", "version": "2.0.3"}}]}, "published": "2025-12-30T13:16:08.750", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/253a3a324e0ebc2825de76a0f5f17b8383b2023d"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/dd4f6bbfa646f258e5bcdfac57a5c413d687f588"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Deferred"}

{"bugzilla": {"description": "kernel: net/sched: flower: fix filter idr initialization", "id": "2426193", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2426193"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.0", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H", "status": "draft"}, "details": ["No description is available for this CVE."], "name": "CVE-2023-54206", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2025-12-30T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2023-54206\nhttps://nvd.nist.gov/vuln/detail/CVE-2023-54206\nhttps://lore.kernel.org/linux-cve-announce/2025123022-CVE-2023-54206-1057@gregkh/T"], "threat_severity": "Moderate"}

{}