{
  "containers": {
    "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": "314bd592085c0720ef519f6edbc5f41440ff78d4",
              "status": "affected",
              "version": "022ac075088366b62e130da5e1b200bc93a47191",
              "versionType": "git"
            },
            {
              "lessThan": "fd4cfa8c8f9a17cdec0539334d28754bc1d8a5d9",
              "status": "affected",
              "version": "022ac075088366b62e130da5e1b200bc93a47191",
              "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": "7.1"
            },
            {
              "lessThan": "7.1",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.5",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1.5",
                  "versionStartIncluding": "7.1",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2",
                  "versionStartIncluding": "7.1",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Reject negative const offsets for buffer pointers\n\nThe verifier rejects variable offsets for PTR_TO_TP_BUFFER and PTR_TO_BUF\naccesses, but it currently accepts a constant negative offset produced by\npointer arithmetic.\n\nCommit 022ac0750883 (\"bpf: use reg-\u003evar_off instead of reg-\u003eoff for\npointers\") moved constant pointer offsets from reg-\u003eoff to reg-\u003evar_off.\nHowever, __check_buffer_access() continued to check only the instruction\noffset. An access with reg-\u003evar_off equal to -8 and an instruction offset\nof zero therefore passes verification.\n\nFor writable raw tracepoints, the access end is also calculated from the\nunsigned reg-\u003evar_off.value. An eight-byte access starting at -8 wraps\nthe calculated end to zero, allowing the program to load and attach\nwithout increasing max_tp_access.\n\nAfter ensuring that reg-\u003evar_off is constant, calculate the effective\naccess start using signed arithmetic and reject it when it is negative.\nUse the validated start to calculate the access end for both\nPTR_TO_TP_BUFFER and PTR_TO_BUF."
        }
      ],
      "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 in bpf_check() during bpf(BPF_PROG_LOAD); the path is bpf_prog_load() \u2192 bpf_check() \u2192 check_mem_access() \u2192 __check_buffer_access() on PTR_TO_TP_BUFFER/PTR_TO_BUF. Per kernel CNA guidance BPF verifier bugs are Local, not network-reachable.\nAC:L - Exploitation is deterministic: pointer arithmetic (e.g. r6 += -8) yields a constant negative reg-\u003evar_off that passes the insn-only check, and unsigned wrap sets max_tp_access/max_rdwr_access to zero. The attacker fully controls program bytecode and triggering with no race or layout dependency.\nPR:L - Affected BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE and BPF_PROG_TYPE_TRACING/BPF_TRACE_ITER programs require CAP_BPF and CAP_PERFMON checked by bpf_token_capable(); BPF tokens delegate these capabilities into a non-init user namespace, so a namespace-local actor can reach bpf_prog_load without init-namespace root.\nUI:N - No victim interaction is required; after loading and attaching the malicious program the attacker triggers execution by reading a BPF iterator fd or causing a writable raw tracepoint to fire, entirely through their own syscalls.\nS:U - The verifier bypass permits out-of-bounds kernel reads/writes adjacent to tracepoint or iterator buffers within the same host kernel security authority; impact is standard kernel memory corruption and privilege escalation, not a VM, container, or IOMMU boundary crossing.\nC:H - Verified loads at negative offsets read up to eight bytes before PTR_TO_TP_BUFFER or PTR_TO_BUF targets, disclosing adjacent kernel stack or kmalloc memory (map keys/values, tracepoint writable buffers); per guidance out-of-bounds kernel reads warrant High confidentiality impact.\nI:H - Writable raw tracepoint programs can store at negative offsets while max_tp_access wraps to zero, and PTR_TO_BUF iterator contexts allow verified writes before map value buffers; these out-of-bounds stores corrupt adjacent kernel memory with a plausible control-flow hijack primitive.\nA:H - Out-of-bounds kernel memory accesses from attached BPF programs commonly provoke kernel oops or panic; the attacker can repeatedly trigger iterator reads or writable raw tracepoints to deny host availability."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-17T05:39:09.532Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/314bd592085c0720ef519f6edbc5f41440ff78d4"
        },
        {
          "url": "https://git.kernel.org/stable/c/fd4cfa8c8f9a17cdec0539334d28754bc1d8a5d9"
        }
      ],
      "title": "bpf: Reject negative const offsets for buffer pointers",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-68462",
    "datePublished": "2026-08-15T05:51:21.948Z",
    "dateReserved": "2026-07-30T09:28:09.395Z",
    "dateUpdated": "2026-08-17T05:39:09.532Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}