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GHSA-HQXW-MM44-GC4R

Vulnerability from github – Published: 2021-08-30 16:16 – Updated: 2022-08-15 20:04
VLAI
Summary
Istio Fragments in Path May Lead to Authorization Policy Bypass
Details

Impact

Istio 1.11.0, 1.10.3 and below, and 1.9.7 and below contain a remotely exploitable vulnerability where an HTTP request with #fragment in the path may bypass Istio’s URI path based authorization policies.

Patches

  • Istio 1.11.1 and above
  • Istio 1.10.4 and above
  • Istio 1.9.8 and above

Workarounds

A Lua filter may be written to normalize the path. This is similar to the Path normalization presented in the Security Best Practices guide.

References

More details can be found in the Istio Security Bulletin

For more information

If you have any questions or comments about this advisory, please email us at istio-security-vulnerability-reports@googlegroups.com

Severity
8.1 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N
Show details on source website
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{
  "affected": [
    {
      "package": {
        "ecosystem": "Go",
        "name": "istio.io/istio"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.9.8"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Go",
        "name": "istio.io/istio"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "1.10.0"
            },
            {
              "fixed": "1.10.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Go",
        "name": "istio.io/istio"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "1.11.0"
            },
            {
              "fixed": "1.11.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.11.0"
      ]
    }
  ],
  "aliases": [
    "CVE-2021-39156"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-706",
      "CWE-863"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2021-08-25T22:28:17Z",
    "nvd_published_at": "2021-08-24T23:15:00Z",
    "severity": "HIGH"
  },
  "details": "### Impact\nIstio 1.11.0, 1.10.3 and below, and 1.9.7 and below contain a remotely exploitable vulnerability where an HTTP request with `#fragment` in the path may bypass Istio\u2019s URI path based authorization policies. \n\n### Patches\n* Istio 1.11.1 and above\n* Istio 1.10.4 and above\n* Istio 1.9.8 and above\n\n### Workarounds\nA Lua filter may be written to normalize the path.  This is similar to the Path normalization presented in the [Security Best Practices](https://istio.io/latest/docs/ops/best-practices/security/#case-normalization) guide.\n\n### References\nMore details can be found in the [Istio Security Bulletin](https://istio.io/latest/news/security/istio-security-2021-008)\n\n### For more information\nIf you have any questions or comments about this advisory, please email us at istio-security-vulnerability-reports@googlegroups.com\n",
  "id": "GHSA-hqxw-mm44-gc4r",
  "modified": "2022-08-15T20:04:30Z",
  "published": "2021-08-30T16:16:14Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/istio/istio/security/advisories/GHSA-hqxw-mm44-gc4r"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-39156"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/istio/istio"
    },
    {
      "type": "WEB",
      "url": "https://istio.io/latest/news/security/istio-security-2021-008"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Istio Fragments in Path May Lead to Authorization Policy Bypass"
}



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