netfilter: nft_meta_bridge: fix stale stack leak via IIFHWADDR register

{
  "id": "46efe7efa96859d828ae922c350dfa002a7c673866eaed8ee646ec91ebd4ff5e",
  "url": "https://osv.dev/vulnerability/CVE-2026-53211",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "netfilter: nft_meta_bridge: fix stale stack leak via IIFHWADDR register",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_meta_bridge: fix stale stack leak via IIFHWADDR register NFT_META_BRI_IIFHWADDR declares its destination register with len = ETH_ALEN (6 bytes), which the register-init tracking rounds up to two 32-bit registers (8 bytes). nft_meta_bridge_get_eval() then does memcpy(dest, br_dev->dev_addr, ETH_ALEN), writing only 6 bytes and leaving the upper 2 bytes of the second register as uninitialised nft_do_chain() stack. A downstream load of that register span leaks those stale bytes to userspace. Zero the second register before the memcpy so the full declared span is written.",
    "evidence": "osv:CVE-2026-53211",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "6.18.36",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "7.0.13",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "CVE-2026-53211",
      "aliases": [
        "CVE-2026-53211"
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "cbd2257dc96e3e46217540fcb095a757ffa20d96"
                },
                {
                  "fixed": "07acb9798477535933bd658ac9fa85b6cb10d995"
                },
                {
                  "fixed": "f1e81d571e375d10e50e852223593493d98c1bac"
                },
                {
                  "fixed": "c7d573551f9286100a055ef696cde6af54549677"
                }
              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-53211.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.18.0"
                },
                {
                  "fixed": "6.18.36"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.19.0"
                },
                {
                  "fixed": "7.0.13"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-53211.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:44.166937721Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/07acb9798477535933bd658ac9fa85b6cb10d995",
        "https://git.kernel.org/stable/c/c7d573551f9286100a055ef696cde6af54549677",
        "https://git.kernel.org/stable/c/f1e81d571e375d10e50e852223593493d98c1bac",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53211.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-53211",
        "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
      ],
      "provider_metadata": {
        "cna_assigner": "Linux",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53211.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-53211",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 511707,
  "published_at": "2026-06-25T08:39:16.234+00:00"
}