GHSA-2PGV-C2R7-F43R

Vulnerability from github – Published: 2026-08-21 12:30 – Updated: 2026-08-21 12:30
VLAI
Details

The filestore backend in pkg/object/file.go, used for file:// stores and as a common juicefs sync destination, derived every operation's target from path(key), which returned either filepath.Join(d.root, key) or filepath.Clean(d.root + key) with no check that the result stayed beneath the root. Put, Get, Head, Delete, Chmod, Chown, Symlink and Readlink all consumed that value directly. Object keys enumerated from a source object store during a sync are not constrained the way local filesystem names are, so a key containing traversal segments causes juicefs to write attacker-supplied content to a path outside the intended local destination, and no error is returned. An operator syncing from a bucket whose contents they do not fully control, such as a shared or public bucket or one an attacker can write to, is therefore exposed to a file write at an attacker-influenced location. The fix changes path() to return an error and rejects any key whose resolved path escapes the root.

Severity
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
7.1 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
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{
  "affected": [],
  "aliases": [
    "CVE-2026-77763"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-22"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-21T11:17:06Z",
    "severity": "HIGH"
  },
  "details": "The filestore backend in pkg/object/file.go, used for file:// stores and as a common juicefs sync destination, derived every operation\u0027s target from path(key), which returned either filepath.Join(d.root, key) or filepath.Clean(d.root + key) with no check that the result stayed beneath the root. Put, Get, Head, Delete, Chmod, Chown, Symlink and Readlink all consumed that value directly. Object keys enumerated from a source object store during a sync are not constrained the way local filesystem names are, so a key containing traversal segments causes juicefs to write attacker-supplied content to a path outside the intended local destination, and no error is returned. An operator syncing from a bucket whose contents they do not fully control, such as a shared or public bucket or one an attacker can write to, is therefore exposed to a file write at an attacker-influenced location. The fix changes path() to return an error and rejects any key whose resolved path escapes the root.",
  "id": "GHSA-2pgv-c2r7-f43r",
  "modified": "2026-08-21T12:30:32Z",
  "published": "2026-08-21T12:30:32Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-77763"
    },
    {
      "type": "WEB",
      "url": "https://github.com/juicedata/juicefs/issues/7401"
    },
    {
      "type": "WEB",
      "url": "https://github.com/juicedata/juicefs/pull/7425"
    },
    {
      "type": "WEB",
      "url": "https://github.com/juicedata/juicefs/commit/0bcd70b3d13088d38127d6fb5750c91be7c4ec16"
    },
    {
      "type": "WEB",
      "url": "https://github.com/juicedata/juicefs"
    },
    {
      "type": "WEB",
      "url": "https://github.com/juicedata/juicefs/blob/v1.4.1/pkg/object/file.go"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/juicefs-local-filestore-backend-joins-object-keys-onto-the-storage-root-without-a-containment-check-allowing-writes-outside-the-configured-directory"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}



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