GHSA-VMM6-W4CF-7F3X

Vulnerability from github – Published: 2020-01-30 21:21 – Updated: 2021-10-20 18:03
VLAI
Summary
Authentication Bypass For Endpoints With Anonymous Access in Opencast
Details

Impact

Using a remember-me cookie with an arbitrary username can cause Opencast to assume proper authentication for that user even if the remember-me cookie was incorrect given that the attacked endpoint also allows anonymous access.

This way, an attacker can, for example, fake a remember-me token, assume the identity of the global system administrator and request non-public content from the search service without ever providing any proper authentication.

Patches

This problem is fixed in Opencast 7.6 and Opencast 8.1

Workarounds

As a workaround for older, unpatched versions, disabling remember-me cookies in etc/security/mh_default_org.xml will mitigate the problem but will obviously also disable this feature without obvious indication. To deactivate this, remove the following line from the security configuration:

<sec:remember-me … />

References

For more information

If you have any questions or comments about this advisory:

  • Open an issue in opencast/opencast
  • For security-relevant information, email us at security@opencast.org
Severity
8.7 (High)
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N
Show details on source website
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{
  "affected": [
    {
      "package": {
        "ecosystem": "Maven",
        "name": "org.opencastproject:opencast-kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "7.6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Maven",
        "name": "org.opencastproject:opencast-kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "8.0"
            },
            {
              "fixed": "8.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2020-5206"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-285"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2020-01-30T21:13:52Z",
    "nvd_published_at": null,
    "severity": "CRITICAL"
  },
  "details": "### Impact\n\nUsing a remember-me cookie with an arbitrary username can cause Opencast to assume proper authentication for that user even if the remember-me cookie was incorrect given that the attacked endpoint also allows anonymous access.\n\nThis way, an attacker can, for example, fake a remember-me token, assume the identity of the global system administrator and request non-public content from the search service without ever providing any proper authentication.\n\n\n### Patches\n\nThis problem is fixed in Opencast 7.6 and Opencast 8.1\n\n\n### Workarounds\n\nAs a workaround for older, unpatched versions, disabling remember-me cookies in `etc/security/mh_default_org.xml` will mitigate the problem but will obviously also disable this feature without obvious indication. To deactivate this, remove the following line from the security configuration:\n\n```xml\n\u003csec:remember-me \u2026 /\u003e\n```\n\n### References\n\n- [Remember-me cookie in the security configuration file](https://github.com/opencast/opencast/blob/161ee619382f144dc35eea211fc6b556025b98e1/etc/security/mh_default_org.xml#L335-L336)\n\n\n### For more information\n\nIf you have any questions or comments about this advisory:\n\n- Open an issue in [opencast/opencast](https://github.com/opencast/opencast/issues)\n- For security-relevant information, email us at security@opencast.org",
  "id": "GHSA-vmm6-w4cf-7f3x",
  "modified": "2021-10-20T18:03:07Z",
  "published": "2020-01-30T21:21:30Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/opencast/opencast/security/advisories/GHSA-vmm6-w4cf-7f3x"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2020-5206"
    },
    {
      "type": "WEB",
      "url": "https://github.com/opencast/opencast/commit/b157e1fb3b35991ca7bf59f0730329fbe7ce82e8"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Authentication Bypass For Endpoints With Anonymous Access in Opencast"
}



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