{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2021-47300",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2024-07-24T17:11:18.549517Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2024-07-24T17:11:23.015Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      },
      {
        "providerMetadata": {
          "dateUpdated": "2024-08-04T05:32:08.540Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://git.kernel.org/stable/c/39f1735c8107ef43a53c4daf82f330d880488d8f"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://git.kernel.org/stable/c/cbb086074dab631ac43f8645cbac1d7b148e05c4"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://git.kernel.org/stable/c/5dd0a6b8582ffbfa88351949d50eccd5b6694ade"
          }
        ],
        "title": "CVE Program Container"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "kernel/bpf/verifier.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "39f1735c8107ef43a53c4daf82f330d880488d8f",
              "status": "affected",
              "version": "ebf7d1f508a73871acf3b2bfbfa1323a477acdb3",
              "versionType": "git"
            },
            {
              "lessThan": "cbb086074dab631ac43f8645cbac1d7b148e05c4",
              "status": "affected",
              "version": "ebf7d1f508a73871acf3b2bfbfa1323a477acdb3",
              "versionType": "git"
            },
            {
              "lessThan": "5dd0a6b8582ffbfa88351949d50eccd5b6694ade",
              "status": "affected",
              "version": "ebf7d1f508a73871acf3b2bfbfa1323a477acdb3",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "kernel/bpf/verifier.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.10"
            },
            {
              "lessThan": "5.10",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.54",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.13.*",
              "status": "unaffected",
              "version": "5.13.6",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "5.14",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.10.54",
                  "versionStartIncluding": "5.10",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.13.6",
                  "versionStartIncluding": "5.10",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.14",
                  "versionStartIncluding": "5.10",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Fix tail_call_reachable rejection for interpreter when jit failed\n\nDuring testing of f263a81451c1 (\"bpf: Track subprog poke descriptors correctly\nand fix use-after-free\") under various failure conditions, for example, when\njit_subprogs() fails and tries to clean up the program to be run under the\ninterpreter, we ran into the following freeze:\n\n  [...]\n  #127/8 tailcall_bpf2bpf_3:FAIL\n  [...]\n  [   92.041251] BUG: KASAN: slab-out-of-bounds in ___bpf_prog_run+0x1b9d/0x2e20\n  [   92.042408] Read of size 8 at addr ffff88800da67f68 by task test_progs/682\n  [   92.043707]\n  [   92.044030] CPU: 1 PID: 682 Comm: test_progs Tainted: G   O   5.13.0-53301-ge6c08cb33a30-dirty #87\n  [   92.045542] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1 04/01/2014\n  [   92.046785] Call Trace:\n  [   92.047171]  ? __bpf_prog_run_args64+0xc0/0xc0\n  [   92.047773]  ? __bpf_prog_run_args32+0x8b/0xb0\n  [   92.048389]  ? __bpf_prog_run_args64+0xc0/0xc0\n  [   92.049019]  ? ktime_get+0x117/0x130\n  [...] // few hundred [similar] lines more\n  [   92.659025]  ? ktime_get+0x117/0x130\n  [   92.659845]  ? __bpf_prog_run_args64+0xc0/0xc0\n  [   92.660738]  ? __bpf_prog_run_args32+0x8b/0xb0\n  [   92.661528]  ? __bpf_prog_run_args64+0xc0/0xc0\n  [   92.662378]  ? print_usage_bug+0x50/0x50\n  [   92.663221]  ? print_usage_bug+0x50/0x50\n  [   92.664077]  ? bpf_ksym_find+0x9c/0xe0\n  [   92.664887]  ? ktime_get+0x117/0x130\n  [   92.665624]  ? kernel_text_address+0xf5/0x100\n  [   92.666529]  ? __kernel_text_address+0xe/0x30\n  [   92.667725]  ? unwind_get_return_address+0x2f/0x50\n  [   92.668854]  ? ___bpf_prog_run+0x15d4/0x2e20\n  [   92.670185]  ? ktime_get+0x117/0x130\n  [   92.671130]  ? __bpf_prog_run_args64+0xc0/0xc0\n  [   92.672020]  ? __bpf_prog_run_args32+0x8b/0xb0\n  [   92.672860]  ? __bpf_prog_run_args64+0xc0/0xc0\n  [   92.675159]  ? ktime_get+0x117/0x130\n  [   92.677074]  ? lock_is_held_type+0xd5/0x130\n  [   92.678662]  ? ___bpf_prog_run+0x15d4/0x2e20\n  [   92.680046]  ? ktime_get+0x117/0x130\n  [   92.681285]  ? __bpf_prog_run32+0x6b/0x90\n  [   92.682601]  ? __bpf_prog_run64+0x90/0x90\n  [   92.683636]  ? lock_downgrade+0x370/0x370\n  [   92.684647]  ? mark_held_locks+0x44/0x90\n  [   92.685652]  ? ktime_get+0x117/0x130\n  [   92.686752]  ? lockdep_hardirqs_on+0x79/0x100\n  [   92.688004]  ? ktime_get+0x117/0x130\n  [   92.688573]  ? __cant_migrate+0x2b/0x80\n  [   92.689192]  ? bpf_test_run+0x2f4/0x510\n  [   92.689869]  ? bpf_test_timer_continue+0x1c0/0x1c0\n  [   92.690856]  ? rcu_read_lock_bh_held+0x90/0x90\n  [   92.691506]  ? __kasan_slab_alloc+0x61/0x80\n  [   92.692128]  ? eth_type_trans+0x128/0x240\n  [   92.692737]  ? __build_skb+0x46/0x50\n  [   92.693252]  ? bpf_prog_test_run_skb+0x65e/0xc50\n  [   92.693954]  ? bpf_prog_test_run_raw_tp+0x2d0/0x2d0\n  [   92.694639]  ? __fget_light+0xa1/0x100\n  [   92.695162]  ? bpf_prog_inc+0x23/0x30\n  [   92.695685]  ? __sys_bpf+0xb40/0x2c80\n  [   92.696324]  ? bpf_link_get_from_fd+0x90/0x90\n  [   92.697150]  ? mark_held_locks+0x24/0x90\n  [   92.698007]  ? lockdep_hardirqs_on_prepare+0x124/0x220\n  [   92.699045]  ? finish_task_switch+0xe6/0x370\n  [   92.700072]  ? lockdep_hardirqs_on+0x79/0x100\n  [   92.701233]  ? finish_task_switch+0x11d/0x370\n  [   92.702264]  ? __switch_to+0x2c0/0x740\n  [   92.703148]  ? mark_held_locks+0x24/0x90\n  [   92.704155]  ? __x64_sys_bpf+0x45/0x50\n  [   92.705146]  ? do_syscall_64+0x35/0x80\n  [   92.706953]  ? entry_SYSCALL_64_after_hwframe+0x44/0xae\n  [...]\n\nTurns out that the program rejection from e411901c0b77 (\"bpf: allow for tailcalls\nin BPF subprograms for x64 JIT\") is buggy since env-\u003eprog-\u003eaux-\u003etail_call_reachable\nis never true. Commit ebf7d1f508a7 (\"bpf, x64: rework pro/epilogue and tailcall\nhandling in JIT\") added a tracker into check_max_stack_depth() which propagates\nthe tail_call_reachable condition throughout the subprograms. This info is then\nassigned to the subprogram\u0027s \n---truncated---"
        }
      ],
      "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"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - The bug is reached only via the local bpf() syscall (BPF_PROG_LOAD \u2192 verifier fixup_call_args, then program execution such as BPF_PROG_TEST_RUN), not by parsing remote network input; BPF is scored Local per kernel CNA guidance.\nAC:L - A CAP_BPF attacker fully controls the bpf2bpf+tailcall program and can force jit_subprogs() failure (e.g., exhausting executable/JIT allocations so bpf_int_jit_compile/bpf_prog_alloc fails), which deterministically falls through to the broken interpreter rejection path with no race required.\nPR:L - bpf-to-bpf calls require bpf_capable() (CAP_BPF/CAP_SYS_ADMIN in init_user_ns); per kernel CNA BPF scoring precedent CAP_BPF-gated loading is Low privilege, not full root/admin.\nUI:N - The attacker loads the crafted program and triggers execution themselves (e.g., BPF_PROG_TEST_RUN or an attach point they control); no separate victim action is required.\nS:U - Impact stays within the host kernel\u2019s BPF/interpreter authority (local memory-safety failure and DoS/privilege escalation); it does not cross a VM, IOMMU, or other distinct security boundary.\nC:H - The fixed failure path produced a KASAN slab-out-of-bounds read in ___bpf_prog_run; per guidance an OOB read is Confidentiality High unless strictly bounded to a few bytes.\nI:H - Unsupported interpreter execution of bpf2bpf combined with tail calls causes unbounded recursive interpreter frames and kernel stack overflow/memory corruption, which under the overestimate rule is treated as Integrity High (exploitable corruption/control-flow impact).\nA:H - The commit documents a kernel freeze with hundreds of recursive ___bpf_prog_run frames and a KASAN-detected crash path, which is Availability High (hang/oops/panic)."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T08:47:09.253Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/39f1735c8107ef43a53c4daf82f330d880488d8f"
        },
        {
          "url": "https://git.kernel.org/stable/c/cbb086074dab631ac43f8645cbac1d7b148e05c4"
        },
        {
          "url": "https://git.kernel.org/stable/c/5dd0a6b8582ffbfa88351949d50eccd5b6694ade"
        }
      ],
      "title": "bpf: Fix tail_call_reachable rejection for interpreter when jit failed",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2021-47300",
    "datePublished": "2024-05-21T14:35:22.040Z",
    "dateReserved": "2024-05-21T13:27:52.132Z",
    "dateUpdated": "2026-08-05T08:47:09.253Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}