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GHSA-26C5-PPR8-F33P

Vulnerability from github – Published: 2023-06-06 16:40 – Updated: 2024-09-24 17:36
VLAI
Summary
Synapse has improper checks for deactivated users during login
Details

Impact

It may be possible for a deactivated user to login when using uncommon configurations.

This only applies if any of the following are true:

Note that the local password database is enabled by default, but it is uncommon to set a user's password after they've been deactivated.

Installations that are configured to only allow login via Single Sign-On (SSO) via CAS, SAML or OpenID Connect (OIDC); or via an external password provider (e.g. LDAP) are not affected.

Patches

  • If using JSON Web Token logins: #15624
  • For other users: #15634

Workarounds

If not using JSON Web Tokens, ensure that deactivated users do not have a password set. This list of users can be queried from PostgreSQL:

SELECT name FROM users WHERE password_hash IS NOT NULL AND deactivated = 1;
Severity
5.4 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
5.3 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
Show details on source website
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{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "matrix-synapse"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.85.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2023-32682"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-287"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2023-06-06T16:40:42Z",
    "nvd_published_at": "2023-06-06T19:15:11Z",
    "severity": "MODERATE"
  },
  "details": "### Impact\nIt may be possible for a deactivated user to login when using uncommon configurations.\n\nThis only applies if any of the following are true:\n\n* [JSON Web Tokens are enabled for login](https://matrix-org.github.io/synapse/latest/jwt.html) via the `jwt_config.enabled` configuration setting\n* The [local password database is enabled](https://matrix-org.github.io/synapse/latest/usage/configuration/config_documentation.html#password_config) via the `password_config.enabled` and `password_config.localdb_enabled` configuration settings *and* a user\u0027s password is [updated via an admin API](https://matrix-org.github.io/synapse/latest/admin_api/user_admin_api.html#create-or-modify-account) after a user is deactivated.\n\n**Note that the local password database is enabled by default**, but it is uncommon to set a user\u0027s password after they\u0027ve been deactivated.\n\nInstallations that are configured to only allow login via Single Sign-On (SSO) via CAS, SAML or OpenID Connect (OIDC); or via an external password provider (e.g. LDAP) are not affected.\n\n### Patches\n\n* If using JSON Web Token logins: #15624\n* For other users: #15634\n\n### Workarounds\n\nIf not using JSON Web Tokens, ensure that deactivated users do not have a password set. This list of users can be queried from PostgreSQL:\n\n```sql\nSELECT name FROM users WHERE password_hash IS NOT NULL AND deactivated = 1;\n```\n\n",
  "id": "GHSA-26c5-ppr8-f33p",
  "modified": "2024-09-24T17:36:26Z",
  "published": "2023-06-06T16:40:42Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/matrix-org/synapse/security/advisories/GHSA-26c5-ppr8-f33p"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-32682"
    },
    {
      "type": "WEB",
      "url": "https://github.com/matrix-org/synapse/issues/12274"
    },
    {
      "type": "WEB",
      "url": "https://github.com/matrix-org/synapse/pull/15624"
    },
    {
      "type": "WEB",
      "url": "https://github.com/matrix-org/synapse/pull/15634"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/matrix-org/synapse"
    },
    {
      "type": "WEB",
      "url": "https://github.com/matrix-org/synapse/releases/tag/v1.85.0"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pypa/advisory-database/tree/main/vulns/matrix-synapse/PYSEC-2023-84.yaml"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/X6DH5A5YEB5LRIPP32OUW25FCGZFCZU2"
    },
    {
      "type": "WEB",
      "url": "https://matrix-org.github.io/synapse/latest/admin_api/user_admin_api.html#create-or-modify-account"
    },
    {
      "type": "WEB",
      "url": "https://matrix-org.github.io/synapse/latest/jwt.html"
    },
    {
      "type": "WEB",
      "url": "https://matrix-org.github.io/synapse/latest/usage/configuration/config_documentation.html#password_config"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Synapse has improper checks for deactivated users during login"
}



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