{
  "schema_version": "1.4.0",
  "id": "GHSA-w6fv-6gcc-x825",
  "modified": "2025-03-19T15:00:20Z",
  "published": "2025-03-17T14:46:56Z",
  "aliases": [
    "CVE-2025-27512"
  ],
  "summary": "Zincati allows unprivileged access to rpm-ostree D-Bus `Deploy()` and `FinalizeDeployment()` methods",
  "details": "### Impact\n\nZincati ships a polkit rule which allows the `zincati` system user to use the following actions:\n- `org.projectatomic.rpmostree1.deploy`: used to deploy updates to the system\n- `org.projectatomic.rpmostree1.finalize-deployment`: used to reboot the system into the deployed update\n\nSince Zincati [v0.0.24](https://github.com/coreos/zincati/releases/tag/v0.0.24), this polkit rule contains a logic error which broadens access of those polkit actions to any unprivileged user rather than just the `zincati` system user.\n\nIn practice, this means that any unprivileged user with access to the system D-Bus socket is able to deploy older Fedora CoreOS versions (which may have other known vulnerabilities). Note that rpm-ostree enforces that the selected version must be from the same branch the system is currently on so this cannot directly be used to deploy an attacker-controlled update payload.\n\nThis primarily impacts users running untrusted workloads with access to the system D-Bus socket. Note that in general, untrusted workloads should not be given this access, whether containerized or not. By default, containers do not have access to the system D-Bus socket.\n\n### Patches\n\nThe logic error is fixed in Zincati v0.0.30. The fix is included in the following FCOS releases:\n- On the `stable` stream: 41.20250302.3.2\n- On the `testing` stream: 41.20250315.2.0\n- On the `next` stream: 42.20250316.1.0\n\n### Workarounds\n\nA workaround is to add the following polkit rule:\n\n```javascript\npolkit.addRule(function(action, subject) {\n    if (action.id == \"org.projectatomic.rpmostree1.deploy\" ||\n        action.id == \"org.projectatomic.rpmostree1.finalize-deployment\" ||\n        action.id == \"org.projectatomic.rpmostree1.cleanup\") {\n        if (subject.user != \"zincati\") {\n                return polkit.Result.NO;\n        }\n    }\n});\n```\n\nto e.g. `/etc/polkit-1/rules.d/00-zincati-fix.rules` (it must sort earlier than `zincati.rules` lexicographically).\n\nNote that this rule will deny all non-root users other than `zincati` from using those actions. If you've added polkit rules to allow e.g. the `core` user or other users, you will need to adjust the policy (or make sure the ordering is appropriate).\n\n### References\n\nThis issue was introduced by [this commit](https://github.com/coreos/zincati/commit/28a43aa2c1edda091ba659677d73c13e6e3ea99d), and is fixed in [v0.0.30](https://github.com/coreos/zincati/releases/tag/v0.0.30).",
  "severity": [
    {
      "type": "CVSS_V4",
      "score": "CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:U"
    }
  ],
  "affected": [
    {
      "package": {
        "ecosystem": "crates.io",
        "name": "zincati"
      },
      "ranges": [
        {
          "type": "ECOSYSTEM",
          "events": [
            {
              "introduced": "0.0.24"
            },
            {
              "fixed": "0.0.30"
            }
          ]
        }
      ],
      "database_specific": {
        "last_known_affected_version_range": "<= 0.0.29"
      }
    }
  ],
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/coreos/zincati/security/advisories/GHSA-w6fv-6gcc-x825"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-27512"
    },
    {
      "type": "WEB",
      "url": "https://github.com/coreos/zincati/commit/01d8e89f799e6ba21bdf7dc668abce23bd0d8f78"
    },
    {
      "type": "WEB",
      "url": "https://github.com/coreos/zincati/commit/28a43aa2c1edda091ba659677d73c13e6e3ea99d"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/coreos/zincati"
    },
    {
      "type": "WEB",
      "url": "https://github.com/coreos/zincati/releases/tag/v0.0.24"
    },
    {
      "type": "WEB",
      "url": "https://github.com/coreos/zincati/releases/tag/v0.0.30"
    }
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-783",
      "CWE-863"
    ],
    "severity": "LOW",
    "github_reviewed": true,
    "github_reviewed_at": "2025-03-17T14:46:56Z",
    "nvd_published_at": "2025-03-17T15:15:44Z"
  }
}