{
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"cveMetadata": {
"cveId": "CVE-2021-47136",
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"state": "PUBLISHED",
"assignerShortName": "Linux",
"dateReserved": "2024-03-04T18:12:48.840Z",
"datePublished": "2024-03-25T09:07:36.064Z",
"dateUpdated": "2026-05-23T15:19:23.773Z"
},
"containers": {
"cna": {
"providerMetadata": {
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux",
"dateUpdated": "2026-05-23T15:19:23.773Z"
},
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: zero-initialize tc skb extension on allocation\n\nFunction skb_ext_add() doesn't initialize created skb extension with any\nvalue and leaves it up to the user. However, since extension of type\nTC_SKB_EXT originally contained only single value tc_skb_ext->chain its\nusers used to just assign the chain value without setting whole extension\nmemory to zero first. This assumption changed when TC_SKB_EXT extension was\nextended with additional fields but not all users were updated to\ninitialize the new fields which leads to use of uninitialized memory\nafterwards. UBSAN log:\n\n[ 778.299821] UBSAN: invalid-load in net/openvswitch/flow.c:899:28\n[ 778.301495] load of value 107 is not a valid value for type '_Bool'\n[ 778.303215] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.12.0-rc7+ #2\n[ 778.304933] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014\n[ 778.307901] Call Trace:\n[ 778.308680] \n[ 778.309358] dump_stack+0xbb/0x107\n[ 778.310307] ubsan_epilogue+0x5/0x40\n[ 778.311167] __ubsan_handle_load_invalid_value.cold+0x43/0x48\n[ 778.312454] ? memset+0x20/0x40\n[ 778.313230] ovs_flow_key_extract.cold+0xf/0x14 [openvswitch]\n[ 778.314532] ovs_vport_receive+0x19e/0x2e0 [openvswitch]\n[ 778.315749] ? ovs_vport_find_upcall_portid+0x330/0x330 [openvswitch]\n[ 778.317188] ? create_prof_cpu_mask+0x20/0x20\n[ 778.318220] ? arch_stack_walk+0x82/0xf0\n[ 778.319153] ? secondary_startup_64_no_verify+0xb0/0xbb\n[ 778.320399] ? stack_trace_save+0x91/0xc0\n[ 778.321362] ? stack_trace_consume_entry+0x160/0x160\n[ 778.322517] ? lock_release+0x52e/0x760\n[ 778.323444] netdev_frame_hook+0x323/0x610 [openvswitch]\n[ 778.324668] ? ovs_netdev_get_vport+0xe0/0xe0 [openvswitch]\n[ 778.325950] __netif_receive_skb_core+0x771/0x2db0\n[ 778.327067] ? lock_downgrade+0x6e0/0x6f0\n[ 778.328021] ? lock_acquire+0x565/0x720\n[ 778.328940] ? generic_xdp_tx+0x4f0/0x4f0\n[ 778.329902] ? inet_gro_receive+0x2a7/0x10a0\n[ 778.330914] ? lock_downgrade+0x6f0/0x6f0\n[ 778.331867] ? udp4_gro_receive+0x4c4/0x13e0\n[ 778.332876] ? lock_release+0x52e/0x760\n[ 778.333808] ? dev_gro_receive+0xcc8/0x2380\n[ 778.334810] ? lock_downgrade+0x6f0/0x6f0\n[ 778.335769] __netif_receive_skb_list_core+0x295/0x820\n[ 778.336955] ? process_backlog+0x780/0x780\n[ 778.337941] ? mlx5e_rep_tc_netdevice_event_unregister+0x20/0x20 [mlx5_core]\n[ 778.339613] ? seqcount_lockdep_reader_access.constprop.0+0xa7/0xc0\n[ 778.341033] ? kvm_clock_get_cycles+0x14/0x20\n[ 778.342072] netif_receive_skb_list_internal+0x5f5/0xcb0\n[ 778.343288] ? __kasan_kmalloc+0x7a/0x90\n[ 778.344234] ? mlx5e_handle_rx_cqe_mpwrq+0x9e0/0x9e0 [mlx5_core]\n[ 778.345676] ? mlx5e_xmit_xdp_frame_mpwqe+0x14d0/0x14d0 [mlx5_core]\n[ 778.347140] ? __netif_receive_skb_list_core+0x820/0x820\n[ 778.348351] ? mlx5e_post_rx_mpwqes+0xa6/0x25d0 [mlx5_core]\n[ 778.349688] ? napi_gro_flush+0x26c/0x3c0\n[ 778.350641] napi_complete_done+0x188/0x6b0\n[ 778.351627] mlx5e_napi_poll+0x373/0x1b80 [mlx5_core]\n[ 778.352853] __napi_poll+0x9f/0x510\n[ 778.353704] ? mlx5_flow_namespace_set_mode+0x260/0x260 [mlx5_core]\n[ 778.355158] net_rx_action+0x34c/0xa40\n[ 778.356060] ? napi_threaded_poll+0x3d0/0x3d0\n[ 778.357083] ? sched_clock_cpu+0x18/0x190\n[ 778.358041] ? __common_interrupt+0x8e/0x1a0\n[ 778.359045] __do_softirq+0x1ce/0x984\n[ 778.359938] __irq_exit_rcu+0x137/0x1d0\n[ 778.360865] irq_exit_rcu+0xa/0x20\n[ 778.361708] common_interrupt+0x80/0xa0\n[ 778.362640] \n[ 778.363212] asm_common_interrupt+0x1e/0x40\n[ 778.364204] RIP: 0010:native_safe_halt+0xe/0x10\n[ 778.365273] Code: 4f ff ff ff 4c 89 e7 e8 50 3f 40 fe e9 dc fe ff ff 48 89 df e8 43 3f 40 fe eb 90 cc e9 07 00 00 00 0f 00 2d 74 05 62 00 fb f4 90 e9 07 00 00 00 0f 00 2d 64 05 62 00 f4 c3 cc cc 0f 1f 44 00\n[ 778.369355] RSP: 0018:ffffffff84407e48 EFLAGS: 00000246\n[ 778.370570] RAX\n---truncated---"
}
],
"affected": [
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "unaffected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"drivers/net/ethernet/mellanox/mlx5/core/en/rep/tc.c",
"drivers/net/ethernet/mellanox/mlx5/core/en_tc.c",
"include/net/pkt_cls.h",
"net/sched/cls_api.c"
],
"versions": [
{
"version": "038ebb1a713d114d54dbf14868a73181c0c92758",
"lessThan": "ac493452e937b8939eaf2d24cac51a4804b6c20e",
"status": "affected",
"versionType": "git"
},
{
"version": "038ebb1a713d114d54dbf14868a73181c0c92758",
"lessThan": "86ab133b695ed7ba1f8786b12f4ca43137ad8c18",
"status": "affected",
"versionType": "git"
},
{
"version": "038ebb1a713d114d54dbf14868a73181c0c92758",
"lessThan": "9453d45ecb6c2199d72e73c993e9d98677a2801b",
"status": "affected",
"versionType": "git"
},
{
"version": "7154bda4cfc1f41b339121475d2b0234141f3492",
"status": "affected",
"versionType": "git"
},
{
"version": "5.7.15",
"lessThan": "5.8",
"status": "affected",
"versionType": "semver"
}
]
},
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "affected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"drivers/net/ethernet/mellanox/mlx5/core/en/rep/tc.c",
"drivers/net/ethernet/mellanox/mlx5/core/en_tc.c",
"include/net/pkt_cls.h",
"net/sched/cls_api.c"
],
"versions": [
{
"version": "5.9",
"status": "affected"
},
{
"version": "0",
"lessThan": "5.9",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "5.10.42",
"lessThanOrEqual": "5.10.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "5.12.9",
"lessThanOrEqual": "5.12.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "5.13",
"lessThanOrEqual": "*",
"status": "unaffected",
"versionType": "original_commit_for_fix"
}
]
}
],
"cpeApplicability": [
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"nodes": [
{
"operator": "OR",
"negate": false,
"cpeMatch": [
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "5.9",
"versionEndExcluding": "5.10.42"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "5.9",
"versionEndExcluding": "5.12.9"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "5.9",
"versionEndExcluding": "5.13"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "5.7.15"
}
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"references": [
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"url": "https://git.kernel.org/stable/c/ac493452e937b8939eaf2d24cac51a4804b6c20e"
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"url": "https://git.kernel.org/stable/c/86ab133b695ed7ba1f8786b12f4ca43137ad8c18"
},
{
"url": "https://git.kernel.org/stable/c/9453d45ecb6c2199d72e73c993e9d98677a2801b"
}
],
"title": "net: zero-initialize tc skb extension on allocation",
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"title": "CVE Program Container",
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"id": "CVE-2021-47136",
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"Automatable": "no"
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"version": "2.0.3",
"timestamp": "2024-09-10T15:55:03.662373Z"
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