{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.1",
    "cveMetadata": {
        "cveId": "CVE-2021-46954",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2024-02-27T18:42:55.937Z",
        "datePublished": "2024-02-27T18:46:56.804Z",
        "dateUpdated": "2024-08-04T05:17:42.983Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2024-05-29T04:59:28.379Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: sch_frag: fix stack OOB read while fragmenting IPv4 packets\n\nwhen 'act_mirred' tries to fragment IPv4 packets that had been previously\nre-assembled using 'act_ct', splats like the following can be observed on\nkernels built with KASAN:\n\n BUG: KASAN: stack-out-of-bounds in ip_do_fragment+0x1b03/0x1f60\n Read of size 1 at addr ffff888147009574 by task ping/947\n\n CPU: 0 PID: 947 Comm: ping Not tainted 5.12.0-rc6+ #418\n Hardware name: Red Hat KVM, BIOS 1.11.1-4.module+el8.1.0+4066+0f1aadab 04/01/2014\n Call Trace:\n  <IRQ>\n  dump_stack+0x92/0xc1\n  print_address_description.constprop.7+0x1a/0x150\n  kasan_report.cold.13+0x7f/0x111\n  ip_do_fragment+0x1b03/0x1f60\n  sch_fragment+0x4bf/0xe40\n  tcf_mirred_act+0xc3d/0x11a0 [act_mirred]\n  tcf_action_exec+0x104/0x3e0\n  fl_classify+0x49a/0x5e0 [cls_flower]\n  tcf_classify_ingress+0x18a/0x820\n  __netif_receive_skb_core+0xae7/0x3340\n  __netif_receive_skb_one_core+0xb6/0x1b0\n  process_backlog+0x1ef/0x6c0\n  __napi_poll+0xaa/0x500\n  net_rx_action+0x702/0xac0\n  __do_softirq+0x1e4/0x97f\n  do_softirq+0x71/0x90\n  </IRQ>\n  __local_bh_enable_ip+0xdb/0xf0\n  ip_finish_output2+0x760/0x2120\n  ip_do_fragment+0x15a5/0x1f60\n  __ip_finish_output+0x4c2/0xea0\n  ip_output+0x1ca/0x4d0\n  ip_send_skb+0x37/0xa0\n  raw_sendmsg+0x1c4b/0x2d00\n  sock_sendmsg+0xdb/0x110\n  __sys_sendto+0x1d7/0x2b0\n  __x64_sys_sendto+0xdd/0x1b0\n  do_syscall_64+0x33/0x40\n  entry_SYSCALL_64_after_hwframe+0x44/0xae\n RIP: 0033:0x7f82e13853eb\n Code: 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 f3 0f 1e fa 48 8d 05 75 42 2c 00 41 89 ca 8b 00 85 c0 75 14 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 75 c3 0f 1f 40 00 41 57 4d 89 c7 41 56 41 89\n RSP: 002b:00007ffe01fad888 EFLAGS: 00000246 ORIG_RAX: 000000000000002c\n RAX: ffffffffffffffda RBX: 00005571aac13700 RCX: 00007f82e13853eb\n RDX: 0000000000002330 RSI: 00005571aac13700 RDI: 0000000000000003\n RBP: 0000000000002330 R08: 00005571aac10500 R09: 0000000000000010\n R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe01faefb0\n R13: 00007ffe01fad890 R14: 00007ffe01fad980 R15: 00005571aac0f0a0\n\n The buggy address belongs to the page:\n page:000000001dff2e03 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x147009\n flags: 0x17ffffc0001000(reserved)\n raw: 0017ffffc0001000 ffffea00051c0248 ffffea00051c0248 0000000000000000\n raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000\n page dumped because: kasan: bad access detected\n\n Memory state around the buggy address:\n  ffff888147009400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00\n  ffff888147009480: f1 f1 f1 f1 04 f2 f2 f2 f2 f2 f2 f2 00 00 00 00\n >ffff888147009500: 00 00 00 00 00 00 00 00 00 00 f2 f2 f2 f2 f2 f2\n                                                              ^\n  ffff888147009580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00\n  ffff888147009600: 00 00 00 00 00 00 00 00 00 00 00 00 00 f2 f2 f2\n\nfor IPv4 packets, sch_fragment() uses a temporary struct dst_entry. Then,\nin the following call graph:\n\n  ip_do_fragment()\n    ip_skb_dst_mtu()\n      ip_dst_mtu_maybe_forward()\n        ip_mtu_locked()\n\nthe pointer to struct dst_entry is used as pointer to struct rtable: this\nturns the access to struct members like rt_mtu_locked into an OOB read in\nthe stack. Fix this changing the temporary variable used for IPv4 packets\nin sch_fragment(), similarly to what is done for IPv6 few lines below."
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "net/sched/sch_frag.c"
                    ],
                    "versions": [
                        {
                            "version": "c129412f74e9",
                            "lessThan": "018bb8da5b58",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "c129412f74e9",
                            "lessThan": "8e6dfb7beeb6",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "c129412f74e9",
                            "lessThan": "31fe34a0118e",
                            "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/sch_frag.c"
                    ],
                    "versions": [
                        {
                            "version": "5.11",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "5.11",
                            "status": "unaffected",
                            "versionType": "custom"
                        },
                        {
                            "version": "5.11.20",
                            "lessThanOrEqual": "5.11.*",
                            "status": "unaffected",
                            "versionType": "custom"
                        },
                        {
                            "version": "5.12.3",
                            "lessThanOrEqual": "5.12.*",
                            "status": "unaffected",
                            "versionType": "custom"
                        },
                        {
                            "version": "5.13",
                            "lessThanOrEqual": "*",
                            "status": "unaffected",
                            "versionType": "original_commit_for_fix"
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/018bb8da5b5888e19585f9b802f036afe643fcef"
                },
                {
                    "url": "https://git.kernel.org/stable/c/8e6dfb7beeb6489ac1365b8a71052e737f5da76e"
                },
                {
                    "url": "https://git.kernel.org/stable/c/31fe34a0118e0acc958c802e830ad5d37ef6b1d3"
                }
            ],
            "title": "net/sched: sch_frag: fix stack OOB read while fragmenting IPv4 packets",
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                "engine": "bippy-a5840b7849dd"
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                            "content": {
                                "id": "CVE-2021-46954",
                                "role": "CISA Coordinator",
                                "options": [
                                    {
                                        "Exploitation": "none"
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                                        "Technical Impact": "partial"
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                                "version": "2.0.3",
                                "timestamp": "2024-02-27T19:36:31.837631Z"
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                    "shortName": "CVE",
                    "dateUpdated": "2024-08-04T05:17:42.983Z"
                },
                "title": "CVE Program Container",
                "references": [
                    {
                        "url": "https://git.kernel.org/stable/c/018bb8da5b5888e19585f9b802f036afe643fcef",
                        "tags": [
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