{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "kernel/bpf/map_in_map.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "3a0f73d27a8d379a8852a378b3c3208143e3b3b2",
              "status": "affected",
              "version": "baefdbdf6812e120c9fba9cfb101d3656f478026",
              "versionType": "git"
            },
            {
              "lessThan": "7c58ace08f180f8e249e714d1623388362f9d807",
              "status": "affected",
              "version": "baefdbdf6812e120c9fba9cfb101d3656f478026",
              "versionType": "git"
            },
            {
              "lessThan": "9a3c3c49c333760c8944dadacbe114c1884546ef",
              "status": "affected",
              "version": "baefdbdf6812e120c9fba9cfb101d3656f478026",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "kernel/bpf/map_in_map.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.18"
            },
            {
              "lessThan": "6.18",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.40",
              "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": "6.18.40",
                  "versionStartIncluding": "6.18",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1.5",
                  "versionStartIncluding": "6.18",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2",
                  "versionStartIncluding": "6.18",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Reject exclusive maps as inner maps in map-in-map\n\nAn exclusive map (created with excl_prog_hash) is bound to a single\nprogram by hash: check_map_prog_compatibility() refuses to load any\nprogram whose digest does not match map-\u003eexcl_prog_sha. That check\nonly runs for maps a program references directly, i.e. its used_maps.\nA map reached at runtime through a map-of-maps is never in used_maps,\nand bpf_map_meta_equal() does not consider excl_prog_sha, so an\nexclusive map can be inserted into a non-exclusive outer map and\nthen looked up and mutated by an unrelated program, bypassing the\nexclusivity guarantee.\n\nFor the signed loader this defeats the metadata map exclusivity check\nadded in the signed loader: the cached map-\u003esha[] is validated against\nthe signed hash while another program on a hostile host rewrites the\nfrozen map\u0027s contents through the outer map."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.1,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - The flaw is reached only through bpf(2) syscalls (BPF_MAP_CREATE, BPF_MAP_UPDATE_ELEM, BPF_PROG_LOAD) and runtime BPF helpers on map-in-map structures, which per kernel guidance is a local attack vector.\nAC:L - Exploitation is a reliable, attacker-controlled sequence (create outer map-of-maps, insert exclusive inner map FD, load program referencing only outer map, lookup/mutate inner map) with no races or layout dependencies.\nPR:L - Triggering the vulnerable map-in-map paths requires local BPF privileges (typically CAP_BPF); per kernel guidance this is Low because CAP_BPF can be obtained by unprivileged users via user namespaces, not only init-namespace root.\nUI:N - No victim interaction is required; a local attacker with BPF access can create the outer map, insert the exclusive inner map, and mutate it through an unrelated loaded program without actions by other users.\nS:U - The impact is bypass of BPF exclusive-map and signed-loader integrity controls within the kernel BPF subsystem, not crossing a VM, container-to-host, or IOMMU security boundary.\nC:H - An unrelated BPF program can bpf_map_lookup_elem() an exclusive inner map via map-in-map indirection and read its full contents, including signed metadata and hashes that must remain confidential to unauthorized programs.\nI:H - The same indirection allows bpf_map_update_elem() on an exclusive map bound to a different program digest, defeating exclusivity and enabling rewrite of signed-loader metadata (map-\u003esha[]) and other protected map state.\nA:N - This is an access-control bypass without memory corruption, use-after-free, or kernel panic; exploitation does not inherently cause crashes, hangs, or denial of kernel availability."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-17T05:46:23.107Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/3a0f73d27a8d379a8852a378b3c3208143e3b3b2"
        },
        {
          "url": "https://git.kernel.org/stable/c/7c58ace08f180f8e249e714d1623388362f9d807"
        },
        {
          "url": "https://git.kernel.org/stable/c/9a3c3c49c333760c8944dadacbe114c1884546ef"
        }
      ],
      "title": "bpf: Reject exclusive maps as inner maps in map-in-map",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-74364",
    "datePublished": "2026-08-15T05:58:46.926Z",
    "dateReserved": "2026-08-15T05:44:03.887Z",
    "dateUpdated": "2026-08-17T05:46:23.107Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}