Low

oras-go: Malicious registry can hijack Bearer token realm to exfiltrate credentials and refresh tokens

Type: advisorySources: OSV

oras-go is a Go library for managing OCI artifacts. Prior to 2.6.1, auth.Client follows the realm URL from a registry's WWW-Authenticate: Bearer challenge without validating the scheme or host, allowing a malicious or compromised registry to cause SSRF to internal networks such as http://169.254.169.254/, http://10.0.0.x/, and http://127.0.0.1/, or to downgrade a registry contacted over https:// to an http:// token endpoint in registry/remote/auth/client.go through Client.Do(), Client.fetchBearerToken(), fetchDistributionToken, and fetchOAuth2Token. This issue is fixed in version 2.6.1.

Products: Not specified
Affected versions: Not specified
Fixed versions: Not specified
CVEs: CVE-2026-48978
Confirmed fixed CVEs: Not specified
Updated in this feed: 3 Nov 2026, 18:11 UTC · Revision 1

Source evidence

oras-go: Malicious registry can hijack Bearer token realm to exfiltrate credentials and refresh tokens

core-osv · Original source

Published 17 Jul 2026, 19:34 UTC

osv:CVE-2026-48978

Complete source record

{
  "id": "3f017821cd02a6ead0a3784b1e61cd92d952632756c6a1477595cf1ed2f3aab8",
  "url": "https://osv.dev/vulnerability/CVE-2026-48978",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "oras-go: Malicious registry can hijack Bearer token realm to exfiltrate credentials and refresh tokens",
    "summary": "oras-go is a Go library for managing OCI artifacts. Prior to 2.6.1, auth.Client follows the realm URL from a registry's WWW-Authenticate: Bearer challenge without validating the scheme or host, allowing a malicious or compromised registry to cause SSRF to internal networks such as http://169.254.169.254/, http://10.0.0.x/, and http://127.0.0.1/, or to downgrade a registry contacted over https:// to an http:// token endpoint in registry/remote/auth/client.go through Client.Do(), Client.fetchBearerToken(), fetchDistributionToken, and fetchOAuth2Token. This issue is fixed in version 2.6.1.",
    "evidence": "osv:CVE-2026-48978",
    "products": [],
    "severity": "low",
    "structured": {
      "id": "CVE-2026-48978",
      "aliases": [
        "CVE-2026-48978",
        "GHSA-xf85-363p-868w",
        "GO-2026-5885"
      ],
      "metrics": [
        {
          "type": "CVSS_V4",
          "score": "CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:A/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/oras-project/oras-go",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "47b7c804cb38a4af659ec735e473d3854c63a3c0"
                },
                {
                  "fixed": "7a9f4b0b9558821b0422152ebe21ae56930fe764"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "2.6.1"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StringRangeExpression"
                  },
                  {
                    "range": [
                      {
                        "fixed": "7a9f4b0b9558821b0422152ebe21ae56930fe764"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  },
                  {
                    "range": [
                      {
                        "fixed": "47b7c804cb38a4af659ec735e473d3854c63a3c0"
                      }
                    ],
                    "source": "REFERENCES_TAG",
                    "original_tag": "v2.6.1"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v2.6.0",
            "v2.5.0",
            "v2.4.0",
            "v2.3.0",
            "v2.2.0",
            "v2.1.0",
            "v2.0.2",
            "v2.0.1",
            "v2.0.0",
            "v2.0.0-rc.6",
            "v2.0.0-rc.5",
            "v2.0.0-rc.4",
            "v2.0.0-rc.3",
            "v2.0.0-rc.2",
            "v2.0.0-rc.1",
            "v2.0.0-alpha",
            "v0.5.0",
            "v0.4.0",
            "v0.3.0",
            "v0.2.0",
            "v0.1.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-48978.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:31.264529960Z",
      "provider": "osv",
      "references": [
        "https://github.com/oras-project/oras-go/releases/tag/v2.6.1",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/48xxx/CVE-2026-48978.json",
        "https://github.com/oras-project/oras-go/security/advisories/GHSA-xf85-363p-868w",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-48978",
        "https://github.com/oras-project/oras-go/commit/7a9f4b0b9558821b0422152ebe21ae56930fe764"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-319",
          "CWE-918"
        ],
        "cna_assigner": "GitHub_M",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/48xxx/CVE-2026-48978.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-48978",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 498296,
  "published_at": "2026-07-17T19:34:53.69+00:00"
}