Elixir protobuf: Unbounded recursion depth in embedded-message decoding

{
  "id": "862fdf852cafc6b28b42fc717792b87845805765011aa7059e51d67b2c26f51f",
  "url": "https://osv.dev/vulnerability/CVE-2026-54451",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Elixir protobuf: Unbounded recursion depth in embedded-message decoding",
    "summary": "Elixir protobuf is a pure Elixir implementation of Google Protobuf. From 0.8.0 until 0.16.1, services that decode attacker-controlled protobuf bytes with Protobuf.Decoder can be taken offline when the schema contains a self-referential or cyclic message type. In lib/protobuf/decoder.ex, Protobuf.Decoder.value_for_field/3 handles an embedded?: true field by recursively entering the decode / build_message / handle_value / value_for_field call chain without enforcing a nesting-depth limit. Deeply nested embedded fields retain non-tail recursive frames, allowing a comparatively small request to consume substantial CPU and memory, pin a BEAM scheduler, and exhaust the node. This issue is fixed in version 0.16.1.",
    "evidence": "osv:CVE-2026-54451",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-54451",
      "aliases": [
        "CVE-2026-54451",
        "GHSA-rv48-qqj5-crxg"
      ],
      "metrics": [
        {
          "type": "CVSS_V4",
          "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/elixir-protobuf/protobuf",
              "type": "GIT",
              "events": [
                {
                  "introduced": "3b251d286dc94745fc6a92fcbf9be03f44bb9b46"
                },
                {
                  "fixed": "786ba702dab5d7263691db57a972b0bb7330606e"
                },
                {
                  "fixed": "352d1769a0ef575a8d18c3f9620609efdb73e2bc"
                },
                {
                  "fixed": "b8efa97790eece3d2d0e8e7c31a45ed409fe5338"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "0.8.0"
                      },
                      {
                        "fixed": "0.16.1"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StringRangeExpression"
                  },
                  {
                    "range": [
                      {
                        "fixed": "352d1769a0ef575a8d18c3f9620609efdb73e2bc"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  },
                  {
                    "range": [
                      {
                        "fixed": "b8efa97790eece3d2d0e8e7c31a45ed409fe5338"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  },
                  {
                    "range": [
                      {
                        "fixed": "786ba702dab5d7263691db57a972b0bb7330606e"
                      }
                    ],
                    "source": "REFERENCES_TAG",
                    "original_tag": "v0.16.1"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v0.16.0",
            "v0.15.0",
            "v0.14.1",
            "v0.14.0",
            "v0.13.0",
            "v0.12.0",
            "v0.11.0",
            "v0.10.0",
            "v0.9.0",
            "v0.8.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-54451.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:49.607435597Z",
      "provider": "osv",
      "references": [
        "https://github.com/elixir-protobuf/protobuf/releases/tag/v0.16.1",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/54xxx/CVE-2026-54451.json",
        "https://github.com/elixir-protobuf/protobuf/security/advisories/GHSA-rv48-qqj5-crxg",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-54451",
        "https://github.com/elixir-protobuf/protobuf/commit/352d1769a0ef575a8d18c3f9620609efdb73e2bc",
        "https://github.com/elixir-protobuf/protobuf/commit/b8efa97790eece3d2d0e8e7c31a45ed409fe5338"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-674"
        ],
        "cna_assigner": "GitHub_M",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/54xxx/CVE-2026-54451.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-54451",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 517979,
  "published_at": "2026-09-17T18:19:25.334+00:00"
}