{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0.3.0"
              },
              {
                "fixed": "0.3.1"
              }
            ],
            "source": [
              "DESCRIPTION",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "2681877faf2ef0df7d95852c2a72e9e972c64b7e"
            },
            {
              "fixed": "15bde4311e31c925a428f34c02b283307619e2a2"
            },
            {
              "fixed": "268b591261a3473ab9b87272963e4dd2fd99d972"
            }
          ],
          "repo": "https://github.com/ash-project/ash_authentication_oauth2_server",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-wprp-8gvj-p6cv"
  ],
  "database_specific": {
    "cna_assigner": "EEF",
    "cwe_ids": [
      "CWE-918"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/82xxx/CVE-2026-82757.json",
    "unresolved_ranges": [
      {
        "extracted_events": [
          {
            "introduced": "e713a9ba816761140c226e2ca55b75c0b93f5984"
          },
          {
            "fixed": "268b591261a3473ab9b87272963e4dd2fd99d972"
          }
        ],
        "source": "AFFECTED_FIELD"
      }
    ]
  },
  "details": "Server-Side Request Forgery (SSRF) vulnerability in ash-project ash_authentication_oauth2_server allows an attacker who controls a client metadata URL and its DNS to make the server connect to internal or loopback addresses.\n\npublic_ip?/1 in AshAuthentication.Oauth2Server.CIMD.ReqFetcher enforces the outbound policy for CIMD metadata fetches. It classified several address forms as publicly routable that are not: IPv4-compatible ::/96 (for example ::127.0.0.1), SIIT IPv4-translated ::ffff:0:0:0/96, and deprecated site-local fec0::/10. A returned AAAA record in one of these ranges passed the policy, so a fetch pinned to that address reached space the policy was meant to block.\n\nThis issue affects ash_authentication_oauth2_server: from 0.3.0 before 0.3.1.",
  "id": "CVE-2026-82757",
  "modified": "2026-09-10T03:30:24.642109962Z",
  "published": "2026-09-07T22:31:34.656Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://cna.erlef.org/cves/CVE-2026-82757.html"
    },
    {
      "type": "WEB",
      "url": "https://github.com"
    },
    {
      "type": "WEB",
      "url": "https://osv.dev/vulnerability/EEF-CVE-2026-82757"
    },
    {
      "type": "WEB",
      "url": "https://repo.hex.pm"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/82xxx/CVE-2026-82757.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/ash-project/ash_authentication_oauth2_server/security/advisories/GHSA-wprp-8gvj-p6cv"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-82757"
    },
    {
      "type": "FIX",
      "url": "https://github.com/ash-project/ash_authentication_oauth2_server/commit/268b591261a3473ab9b87272963e4dd2fd99d972"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/ash-project/ash_authentication_oauth2_server"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "ash_authentication_oauth2_server CIMD fetcher classifies IPv4-in-IPv6 and site-local addresses as public, allowing SSRF"
}