Unbounded range expansion in cron describe causes memory exhaustion in oban_web

{
  "id": "c2f61cba4a099cd699aa52c266ce563a2ac0f7046259a86369924e6da46c89aa",
  "url": "https://osv.dev/vulnerability/CVE-2026-48593",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Unbounded range expansion in cron describe causes memory exhaustion in oban_web",
    "summary": "Uncontrolled Resource Consumption vulnerability in oban-bg oban_web ('Elixir.Oban.Web.CronExpr' modules) allows memory exhaustion via unbounded cron range expansion. An attacker with access to schedule cron jobs can submit a malicious cron expression such as \"0 0 1-100000000 * *\". When a user with dashboard access views the cron job list, 'Elixir.Oban.Web.CronExpr':describe/1 is called to render the expression. parse_range/1 parses both range endpoints via Integer.parse/1 with no bounds check, and the downstream helpers expand_dom_parts/1 and expand_dow_parts/1 materialise the range eagerly via Enum.to_list/1, causing allocation of ~2.4 GB and stalling or crashing the BEAM node. A sibling helper extract_dom_values already validates range bounds, but the expansion helpers do not. This issue affects oban_web: from 2.12.0 before 2.12.5.",
    "evidence": "osv:CVE-2026-48593",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2026-48593",
      "aliases": [
        "CVE-2026-48593",
        "EEF-CVE-2026-48593",
        "GHSA-6xh2-93p9-vqh4"
      ],
      "metrics": [
        {
          "type": "CVSS_V4",
          "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/oban-bg/oban_web",
              "type": "GIT",
              "events": [
                {
                  "introduced": "f23d19f035a36430f898c35fcd2168784c427a59"
                },
                {
                  "fixed": "a01100b9405fa62009bc1674d5b2bd2acc27e07e"
                },
                {
                  "fixed": "9998b7e284e02fdd4645dd6231760038e63b584d"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "2.12.0"
                      },
                      {
                        "fixed": "2.12.5"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StandardRange"
                  },
                  {
                    "range": [
                      {
                        "fixed": "9998b7e284e02fdd4645dd6231760038e63b584d"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  }
                ]
              }
            },
            {
              "repo": "https://github.com/oban-bg/oban_web.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "a97c7960bb389b05aaab4cf8042985f02ceddc24"
                },
                {
                  "fixed": "9998b7e284e02fdd4645dd6231760038e63b584d"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "a97c7960bb389b05aaab4cf8042985f02ceddc24"
                      },
                      {
                        "fixed": "9998b7e284e02fdd4645dd6231760038e63b584d"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StandardRange"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v2.12.4",
            "v2.12.3",
            "v2.12.2",
            "v2.12.1",
            "v2.12.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-48593.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:34.706733675Z",
      "provider": "osv",
      "references": [
        "https://cna.erlef.org/cves/CVE-2026-48593.html",
        "https://github.com",
        "https://osv.dev/vulnerability/EEF-CVE-2026-48593",
        "https://repo.hex.pm",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/48xxx/CVE-2026-48593.json",
        "https://github.com/oban-bg/oban_web/security/advisories/GHSA-6xh2-93p9-vqh4",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-48593",
        "https://github.com/oban-bg/oban_web/commit/9998b7e284e02fdd4645dd6231760038e63b584d",
        "https://github.com/oban-bg/oban_web.git"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-400"
        ],
        "cna_assigner": "EEF",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/48xxx/CVE-2026-48593.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-48593",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 501935,
  "published_at": "2026-05-26T19:46:43.98+00:00"
}