Axios: ReDoS (O(N²)) in shouldBypassProxy host normalization, reachable via untrusted redirect Location

{
  "id": "c25beb8677cc266cd0137716e846ed14fe3eca51064abb80d13d03c036d4db0a",
  "url": "https://osv.dev/vulnerability/CVE-2026-101906",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Axios: ReDoS (O(N²)) in shouldBypassProxy host normalization, reachable via untrusted redirect Location",
    "summary": "Axios is a promise-based HTTP client for the browser and Node.js. From 1.15.0 until 1.20.0, Axios shouldBypassProxy applies a quadratic trailing-dot regular expression to redirect hostnames. HTTP_PROXY or HTTPS_PROXY is configured, NO_PROXY or no_proxy is non-empty, redirects are followed, and a crafted redirect Location contains many dots followed by a non-dot character. Hostname.replace(/.+$/, '') backtracks quadratically while processing the crafted redirect hostname. Synchronous regular-expression processing can block the Node.js event loop and cause denial of service. This issue is fixed in version 1.20.0.",
    "evidence": "osv:CVE-2026-101906",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-101906",
      "aliases": [
        "CVE-2026-101906",
        "GHSA-mghh-pgcx-3jjj"
      ],
      "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/axios/axios",
              "type": "GIT",
              "events": [
                {
                  "introduced": "772a4e54ecc4cc2421e2b746daff0aca10f359d7"
                },
                {
                  "fixed": "84a9f3b9a4f3244b8c8e818f557d64c7b964fb25"
                },
                {
                  "fixed": "d19040bda7a8be2f82c3c6e1a5bc03917daee39a"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "1.15.0"
                      },
                      {
                        "fixed": "1.20.0"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StringRangeExpression"
                  },
                  {
                    "range": [
                      {
                        "fixed": "d19040bda7a8be2f82c3c6e1a5bc03917daee39a"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  },
                  {
                    "range": [
                      {
                        "fixed": "84a9f3b9a4f3244b8c8e818f557d64c7b964fb25"
                      }
                    ],
                    "source": "REFERENCES_TAG",
                    "original_tag": "v1.20.0"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v1.19.0",
            "v1.18.1",
            "v1.18.0",
            "v1.17.0",
            "v1.16.1",
            "v1.16.0",
            "v1.15.2",
            "v1.15.1",
            "v1.15.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-101906.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:48.874562320Z",
      "provider": "osv",
      "references": [
        "https://github.com/axios/axios/releases/tag/v1.20.0",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/101xxx/CVE-2026-101906.json",
        "https://github.com/axios/axios/security/advisories/GHSA-mghh-pgcx-3jjj",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-101906",
        "https://github.com/axios/axios/commit/d19040bda7a8be2f82c3c6e1a5bc03917daee39a",
        "https://github.com/axios/axios/pull/11141"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-1333",
          "CWE-400"
        ],
        "cna_assigner": "GitHub_M",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/101xxx/CVE-2026-101906.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-101906",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 516948,
  "published_at": "2026-09-28T17:32:40.772+00:00"
}