CWE-61

{
  "affected": [],
  "aliases": [
    "CVE-2024-1933"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-61"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-03-26T13:15:45Z",
    "severity": "HIGH"
  },
  "details": "Insecure UNIX Symbolic Link (Symlink) Following in TeamViewer Remote Client prior Version 15.52 for macOS allows an attacker with unprivileged access, to potentially elevate privileges or conduct a denial-of-service-attack by overwriting the symlink.",
  "id": "GHSA-j4mm-f543-fj92",
  "modified": "2024-03-26T15:30:49Z",
  "published": "2024-03-26T15:30:49Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-1933"
    },
    {
      "type": "WEB",
      "url": "https://www.teamviewer.com/de/resources/trust-center/security-bulletins/tv-2024-1002"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 0.4.44"
      },
      "package": {
        "ecosystem": "crates.io",
        "name": "tar"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.4.45"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-33056"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-61"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-03-20T17:25:09Z",
    "nvd_published_at": "2026-03-20T08:16:11Z",
    "severity": "MODERATE"
  },
  "details": "## Summary\n\nWhen unpacking a tar archive, the `tar` crate\u0027s `unpack_dir` function uses `fs::metadata()` to check whether a path that already exists is a directory. Because `fs::metadata()` follows symbolic links, a crafted tarball containing a symlink entry followed by a directory entry with the same name causes the crate to treat the symlink target as a valid existing directory \u2014 and subsequently apply `chmod` to it. This allows an attacker to modify the permissions of arbitrary directories outside the extraction root.\n\n## Reproducer\n\nA malicious tarball contains two entries: (1) a symlink `foo` pointing to an arbitrary external directory, and (2) a directory entry `foo/.` (or just `foo`). When unpacked, `create_dir(\"foo\")` fails with `EEXIST` because the symlink is already on disk. The `fs::metadata()` check then follows the symlink, sees a directory at the target, and allows processing to continue. The directory entry\u0027s mode bits are then applied via `chmod`, which also follows the symlink \u2014 modifying the permissions of the external target directory.\n\n## Fix \n\nThe fix is very simple, we now use `fs::symlink_metadata()` in `unpack_dir`, so symlinks are detected and rejected rather than followed.\n\n## Credit\n\nThis issue was reported by @xokdvium - thank you!",
  "id": "GHSA-j4xf-2g29-59ph",
  "modified": "2026-03-25T18:36:33Z",
  "published": "2026-03-20T17:25:09Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/alexcrichton/tar-rs/security/advisories/GHSA-j4xf-2g29-59ph"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-33056"
    },
    {
      "type": "WEB",
      "url": "https://github.com/alexcrichton/tar-rs/commit/17b1fd84e632071cb8eef9d3709bf347bd266446"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/alexcrichton/tar-rs"
    },
    {
      "type": "WEB",
      "url": "https://rustsec.org/advisories/RUSTSEC-2026-0067.html"
    }
  ],
  "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:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "tar-rs `unpack_in` can chmod arbitrary directories by following symlinks"
}

{
  "affected": [],
  "aliases": [
    "CVE-2024-47515"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-61"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-12-24T04:15:05Z",
    "severity": "HIGH"
  },
  "details": "A vulnerability was found in Pagure. Support of symbolic links during repository archiving of repositories allows the disclosure of local files. This flaw allows a malicious user to take advantage of the Pagure instance.",
  "id": "GHSA-jc9g-44f2-xqh4",
  "modified": "2025-02-06T09:31:46Z",
  "published": "2024-12-24T06:30:42Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-47515"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/security/cve/CVE-2024-47515"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2315806"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N",
      "type": "CVSS_V3"
    }
  ]
}

{
  "affected": [
    {
      "package": {
        "ecosystem": "Go",
        "name": "github.com/opencontainers/runc"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.1.14"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Go",
        "name": "github.com/opencontainers/runc"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "1.2.0-rc.1"
            },
            {
              "fixed": "1.2.0-rc.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2024-45310"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-363",
      "CWE-61"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2024-09-03T19:49:32Z",
    "nvd_published_at": "2024-09-03T19:15:15Z",
    "severity": "MODERATE"
  },
  "details": "### Impact\nrunc 1.1.13 and earlier as well as 1.2.0-rc2 and earlier can be tricked into\ncreating empty files or directories in arbitrary locations in the host\nfilesystem by sharing a volume between two containers and exploiting a race\nwith os.MkdirAll. While this can be used to create empty files, existing\nfiles **will not** be truncated.\n\nAn attacker must have the ability to start containers using some kind of custom\nvolume configuration. Containers using user namespaces are still affected, but\nthe scope of places an attacker can create inodes can be significantly reduced.\nSufficiently strict LSM policies (SELinux/Apparmor) can also in principle block\nthis attack -- we suspect the industry standard SELinux policy may restrict\nthis attack\u0027s scope but the exact scope of protection hasn\u0027t been analysed.\n\nThis is exploitable using runc directly as well as through Docker and\nKubernetes.\n\nThe CVSS score for this vulnerability is\nCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:N/I:L/A:N (Low severity, 3.6).\n\n### Workarounds\nUsing user namespaces restricts this attack fairly significantly such that the\nattacker can only create inodes in directories that the remapped root\nuser/group has write access to. Unless the root user is remapped to an actual\nuser on the host (such as with rootless containers that don\u0027t use\n/etc/sub[ug]id), this in practice means that an attacker would only be able to\ncreate inodes in world-writable directories.\n\nA strict enough SELinux or AppArmor policy could in principle also restrict the\nscope if a specific label is applied to the runc runtime, though we haven\u0027t\nthoroughly tested to what extent the standard existing policies block this\nattack nor what exact policies are needed to sufficiently restrict this attack.\n\n### Patches\nFixed in runc v1.1.14 and v1.2.0-rc3.\n\n* `main` patches:\n  * https://github.com/opencontainers/runc/pull/4359\n  *  https://github.com/opencontainers/runc/commit/63c2908164f3a1daea455bf5bcd8d363d70328c7\n* `release-1.1` patches:\n  * https://github.com/opencontainers/runc/commit/8781993968fd964ac723ff5f360b6f259e809a3e\n  * https://github.com/opencontainers/runc/commit/f0b652ea61ff6750a8fcc69865d45a7abf37accf\n\n### Credits\nThanks to Rodrigo Campos Catelin (@rata) and Alban Crequy (@alban) from\nMicrosoft for discovering and reporting this vulnerability.",
  "id": "GHSA-jfvp-7x6p-h2pv",
  "modified": "2025-02-21T21:03:04Z",
  "published": "2024-09-03T19:49:32Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/opencontainers/runc/security/advisories/GHSA-jfvp-7x6p-h2pv"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-45310"
    },
    {
      "type": "WEB",
      "url": "https://github.com/opencontainers/runc/pull/4359"
    },
    {
      "type": "WEB",
      "url": "https://github.com/opencontainers/runc/commit/63c2908164f3a1daea455bf5bcd8d363d70328c7"
    },
    {
      "type": "WEB",
      "url": "https://github.com/opencontainers/runc/commit/8781993968fd964ac723ff5f360b6f259e809a3e"
    },
    {
      "type": "WEB",
      "url": "https://github.com/opencontainers/runc/commit/f0b652ea61ff6750a8fcc69865d45a7abf37accf"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/opencontainers/runc"
    },
    {
      "type": "WEB",
      "url": "https://security.netapp.com/advisory/ntap-20250221-0008"
    },
    {
      "type": "WEB",
      "url": "http://www.openwall.com/lists/oss-security/2024/09/03/1"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:N/I:L/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N/U:Green",
      "type": "CVSS_V4"
    }
  ],
  "summary": "runc can be confused to create empty files/directories on the host"
}

{
  "affected": [
    {
      "package": {
        "ecosystem": "crates.io",
        "name": "cargo"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.97.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-5223"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-61"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-06-26T21:48:43Z",
    "nvd_published_at": "2026-05-25T10:16:15Z",
    "severity": "MODERATE"
  },
  "details": "The Rust Security Response Team was notified that Cargo incorrectly handled symlinks inside of crate tarballs downloaded from third-party registries, allowing a malicious crate to override the source code of another crate from the same registry.\n\nThis vulnerability is tracked as CVE-2026-5223. The severity of the vulnerability is **medium** for users of third-party registries. Users of crates.io are **not affected**, as crates.io forbids uploading crates containing any symlink.\n\n## Overview\n\nWhen building a crate, Cargo extracts its source code in a local cache (stored within `~/.cargo`), reusing it for any future build. Cargo includes protections to prevent any file from being extracted outside of the crate\u0027s own cache directory.\n\nIt was discovered that it\u0027s possible to craft a malicious tarball able to extract files one level below the crate\u0027s own cache directory. With the way the cache is structured, that allowed the malicious crate to override the cache of other crates belonging to the same registry.\n\n## Mitigations\n\nRust 1.96.0, to be released on May 28th, 2026, will update Cargo to reject extracting *any* symlink within crate tarballs, regardless of whether they come from crates.io (which already forbids them) or third-party registries. Note that Cargo never added symlinks when running `cargo package` or `cargo publish`, so the impact of this should be minimal.\n\nUsers who are not able to upgrade to the most recent Rust version are recommended to audit the contents of their registry for the presence of any symlink, and to configure their registry to reject symlink (if such option is available).\n\n## Affected versions\n\nAll versions of Cargo shipped before Rust 1.96.0 are affected.\n\n## Acknowledgements\n\nCargo would like to thank Christos Papakonstantinou for reporting this to us according to the [Rust security policy][1].\n\nCargo also wants to thank the members of the Rust project who helped address the vulnerability: Josh Triplett for developing the fix; Arlo Siemsen for reviewing the fix; Emily Albini for writing this advisory; Emily Albini, Josh Stone and Manish Goregaokar for coordinating the disclosure; Ed Page and Eric Huss for advising during the disclosure.\n\n[1]: https://rust-lang.org/policies/security",
  "id": "GHSA-jq42-7mfv-hm57",
  "modified": "2026-06-26T21:48:43Z",
  "published": "2026-06-26T21:48:43Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/rust-lang/cargo/security/advisories/GHSA-jq42-7mfv-hm57"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-5223"
    },
    {
      "type": "WEB",
      "url": "https://github.com/rust-lang/cargo/pull/17031"
    },
    {
      "type": "WEB",
      "url": "https://blog.rust-lang.org/2026/05/25/cve-2026-5223"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/rust-lang/cargo"
    },
    {
      "type": "WEB",
      "url": "https://groups.google.com/g/rustlang-security-announcements/c/IB74S7Yksg8"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:N/SC:H/SI:H/SA:H",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Cargo crates in third party registries can override the cached source of other crates"
}

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "aiohttp"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "3.10.0b1"
            },
            {
              "fixed": "3.10.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2024-42367"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-61"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2024-08-09T16:49:58Z",
    "nvd_published_at": "2024-08-12T13:38:34Z",
    "severity": "MODERATE"
  },
  "details": "### Summary\nStatic routes which contain files with compressed variants (`.gz` or `.br` extension) were vulnerable to path traversal outside the root directory if those variants are symbolic links.\n\n### Details\nThe server protects static routes from path traversal outside the root directory when `follow_symlinks=False` (default).  It does this by resolving the requested URL to an absolute path and then checking that path relative to the root.  However, these checks are not performed when looking for compressed variants in the `FileResponse` class, and symbolic links are then automatically followed when performing `Path.stat()` and `Path.open()` to send the file.\n\n### Impact\nServers with static routes that contain compressed variants as symbolic links, pointing outside the root directory, or that permit users to upload or create such links, are impacted.\n\n----\n\nPatch: https://github.com/aio-libs/aiohttp/pull/8653/files",
  "id": "GHSA-jwhx-xcg6-8xhj",
  "modified": "2025-06-09T12:17:20Z",
  "published": "2024-08-09T16:49:58Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/aio-libs/aiohttp/security/advisories/GHSA-jwhx-xcg6-8xhj"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-42367"
    },
    {
      "type": "WEB",
      "url": "https://github.com/aio-libs/aiohttp/pull/8653"
    },
    {
      "type": "WEB",
      "url": "https://github.com/aio-libs/aiohttp/commit/ce2e9758814527589b10759a20783fb03b98339f"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/aio-libs/aiohttp"
    },
    {
      "type": "WEB",
      "url": "https://github.com/aio-libs/aiohttp/blob/e0ff5246e1d29b7710ab1a2bbc972b48169f1c05/aiohttp/web_fileresponse.py#L177"
    },
    {
      "type": "WEB",
      "url": "https://github.com/aio-libs/aiohttp/blob/e0ff5246e1d29b7710ab1a2bbc972b48169f1c05/aiohttp/web_urldispatcher.py#L674"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "In aiohttp, compressed files as symlinks are not protected from path traversal"
}

{
  "affected": [],
  "aliases": [
    "CVE-2021-32518"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-59",
      "CWE-61"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2021-07-07T14:15:00Z",
    "severity": "HIGH"
  },
  "details": "A vulnerability in share_link in QSAN Storage Manager allows remote attackers to create a symbolic link then access arbitrary files.",
  "id": "GHSA-m543-3mp9-rfgf",
  "modified": "2022-07-03T00:00:23Z",
  "published": "2022-05-24T19:07:03Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-32518"
    },
    {
      "type": "WEB",
      "url": "https://www.twcert.org.tw/tw/cp-132-4874-79edc-1.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}

{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "npm"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "6.13.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2019-16775"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-59",
      "CWE-61"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2020-06-17T16:30:50Z",
    "nvd_published_at": "2019-12-13T01:15:00Z",
    "severity": "HIGH"
  },
  "details": "Versions of the npm CLI prior to 6.13.3 are vulnerable to an Arbitrary File Write. It fails to prevent access to folders outside of the intended node_modules folder through the bin field. A properly constructed entry in the package.json bin field would allow a package publisher to create files on a user\u0027s system when the package is installed. It is only possible to affect files that the user running `npm install` has access to and it is not possible to over write files that already exist on disk.\n\nThis behavior is still possible through install scripts. This vulnerability bypasses a user using the --ignore-scripts install option.\n\n\n## Recommendation\n\nUpgrade to version 6.13.3 or later.",
  "id": "GHSA-m6cx-g6qm-p2cx",
  "modified": "2021-10-21T21:16:09Z",
  "published": "2019-12-13T15:39:19Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/npm/cli/security/advisories/GHSA-m6cx-g6qm-p2cx"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2019-16775"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHEA-2020:0330"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2020:0573"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2020:0579"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2020:0597"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2020:0602"
    },
    {
      "type": "WEB",
      "url": "https://blog.npmjs.org/post/189618601100/binary-planting-with-the-npm-cli"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/advisories/GHSA-m6cx-g6qm-p2cx"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/npm/cli"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/Z36UKPO5F3PQ3Q2POMF5LEKXWAH5RUFP"
    },
    {
      "type": "WEB",
      "url": "https://www.npmjs.com/advisories/1434"
    },
    {
      "type": "WEB",
      "url": "https://www.oracle.com/security-alerts/cpujan2020.html"
    },
    {
      "type": "WEB",
      "url": "https://www.oracle.com/security-alerts/cpuoct2021.html"
    },
    {
      "type": "WEB",
      "url": "http://lists.opensuse.org/opensuse-security-announce/2020-01/msg00027.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Arbitrary File Write in npm"
}

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "python-dotenv"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.2.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-28684"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-59",
      "CWE-61"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-04-21T14:38:57Z",
    "nvd_published_at": "2026-04-20T17:16:33Z",
    "severity": "MODERATE"
  },
  "details": "### Summary\n\n`set_key()` and `unset_key()` in python-dotenv follow symbolic links when rewriting `.env` files, allowing a local attacker to overwrite arbitrary files via a crafted symlink when a cross-device rename fallback is triggered.\n\n\n### Details\n\nThe `rewrite()` context manager in `dotenv/main.py` is used by both `set_key()` and `unset_key()` to safely modify `.env` files. It works by writing to a temporary file (created in the system\u0027s default temp directory, typically `/tmp`) and then using `shutil.move()` to replace the original file.\n\nWhen the `.env` path is a symbolic link and the temp directory resides on a different filesystem than the target (a common configuration on Linux systems using tmpfs for `/tmp`), the following sequence occurs:\n\n1. `shutil.move()` first attempts `os.rename()`, which fails with an `OSError` because atomic renames cannot cross device boundaries.\n2. On failure, `shutil.move()` falls back to `shutil.copy2()` followed by `os.unlink()`.\n3. `shutil.copy2()` calls `shutil.copyfile()` with `follow_symlinks=True` by default.\n4. This causes the content to be written to the **symlink target** rather than replacing the symlink itself.\n\nAn attacker who has write access to the directory containing a `.env` file can pre-place a symlink pointing to any file that the application process has write access to. When the application (or a privileged process such as a deploy script, Docker entrypoint, or CI pipeline) calls `set_key()` or `unset_key()`, the symlink target is overwritten with the new `.env` content.\n\nThis vulnerability does not require a race condition and is fully deterministic once the preconditions are met.\n\n### Impact\nThe primary impacts are to **integrity** and **availability**:\n\n- **File overwrite / destruction (DoS):** An attacker can cause an application or privileged process to corrupt or destroy configuration files, database configs, or other sensitive files it would not normally have access to modify.\n- **Integrity violation:** The target file\u0027s original content is replaced with `.env`-formatted content controlled by the attacker.\n- **Potential privilege escalation:** In scenarios where a privileged process (running as root or a service account) calls `set_key()`, the attacker can leverage this to write to files beyond their own access level.\n\nThe scope of impact depends on the application using python-dotenv and the privileges under which it runs.\n\n\n### Proof of Concept\n\nThe following script demonstrates the vulnerability. It requires `/tmp` and the user\u0027s home directory to reside on different devices (common on systemd-based Linux systems with tmpfs).\n\n```python\nimport os\nimport sys\nimport tempfile\nfrom dotenv import set_key\n\n# Pre-condition: /tmp must be on a different device than the target directory.\ntmp_dev = os.stat(\"/tmp\").st_dev\nhome_dev = os.stat(os.path.expanduser(\"~\")).st_dev\nassert tmp_dev != home_dev, \"Skipped: /tmp and ~ are on the same device (no cross-device move)\"\n\nwith tempfile.TemporaryDirectory(dir=os.path.expanduser(\"~\")) as workdir:\n    # File an attacker wants to overwrite\n    target = os.path.join(workdir, \"victim_config.txt\")\n    with open(target, \"w\") as f:\n        f.write(\"DB_PASSWORD=supersecret\\n\")\n\n    # Attacker pre-places a symlink at the path the application will use as .env\n    env_symlink = os.path.join(workdir, \".env\")\n    os.symlink(target, env_symlink)\n\n    before = open(target).read()\n\n    # Application writes a new key -- triggers the cross-device fallback\n    set_key(env_symlink, \"INJECTED\", \"attacker_value\")\n\n    after = open(target).read()\n\n    print(\"Before:\", repr(before))\n    print(\"After: \", repr(after))\n    print(\"Symlink target overwritten:\", target)\n```\n\n**Expected output:**\n```\nBefore: \u0027DB_PASSWORD=supersecret\\n\u0027\nAfter:  \"DB_PASSWORD=supersecret\\nINJECTED=\u0027attacker_value\u0027\\n\"\nSymlink target overwritten: /home/user/tmp806nut2g/victim_config.txt\n```\n\n### Remediation\n\nThe fix changes the `rewrite()` context manager in the following ways:\n\n1. **Symlinks are no longer followed by default.** When the `.env` path is a symlink, `rewrite()` now resolves it to the real path before proceeding, or (by default) operates on the symlink entry itself rather than the target.\n2. **A `follow_symlinks: bool = False` parameter** is added to `set_key()` and `unset_key()` for users who explicitly need the old behavior.\n3. **Temp files are written in the same directory** as the target `.env` file (instead of the system temp directory), eliminating the cross-device rename condition entirely.\n4. **`os.replace()` is used instead of `shutil.move()`**, providing atomic replacement without symlink-following fallback behavior.\n\nUsers are advised to upgrade to the patched version as soon as it is available on PyPI.\n\n### Timeline\n\n| Date             | Event                                                                                                                                                                 |\n| ------------ | ---------------------------------------------------------------------------------------------------- |\n| 2026-01-09  | Initial report received from Giorgos Tsigourakos regarding a separate, unrelated issue also located in `rewrite()` |\n| 2026-01-10   | Co-maintainer acknowledged report, requested clarification                                                         |\n| 2026-01-11    | Initial report assessed as not exploitable and closed                                                              |\n| 2026-02-24  | Reporter identified new, distinct cross-device symlink attack vector with deterministic exploitation               |\n| 2026-02-26  | Co-maintainer confirmed vulnerability and shared draft patch                                                       |\n| 2026-02-26  | Reporter validated fix with monkeypatched PoC, proposed CVSS                                                       |\n| 2026-03-01   | Patch merged to main                                                                                               |\n| 2026-03-01   | Patched version released to PyPI                                                                                   |\n| 2026-04-20   | Advisory published                                                                                                 |\n\n### Patches\n\nUpgrade to v.1.2.2 or use the patch from https://github.com/theskumar/python-dotenv/commit/790c5c02991100aa1bf41ee5330aca75edc51311.patch",
  "id": "GHSA-mf9w-mj56-hr94",
  "modified": "2026-04-21T14:38:57Z",
  "published": "2026-04-21T14:38:57Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/theskumar/python-dotenv/security/advisories/GHSA-mf9w-mj56-hr94"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-28684"
    },
    {
      "type": "WEB",
      "url": "https://github.com/theskumar/python-dotenv/commit/790c5c02991100aa1bf41ee5330aca75edc51311"
    },
    {
      "type": "WEB",
      "url": "https://github.com/theskumar/python-dotenv/commit/790c5c02991100aa1bf41ee5330aca75edc51311.patch"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/theskumar/python-dotenv"
    },
    {
      "type": "WEB",
      "url": "https://github.com/theskumar/python-dotenv/releases/tag/v1.2.2"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:N/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "python-dotenv: Symlink following in set_key allows arbitrary file overwrite via cross-device rename fallback"
}

{
  "affected": [],
  "aliases": [
    "CVE-2025-53881"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-61"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-10-02T14:15:45Z",
    "severity": "MODERATE"
  },
  "details": "A UNIX Symbolic Link (Symlink) Following vulnerability in logrotate config in the exim package allowed privilege escalation from mail user/group to root.This issue affects Tumbleweed: from ? before 4.98.2-lp156.248.1.",
  "id": "GHSA-mj4q-r4hv-qwvc",
  "modified": "2025-10-02T15:31:16Z",
  "published": "2025-10-02T15:31:16Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-53881"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.suse.com/show_bug.cgi?id=CVE-2025-53881"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:L/VA:L/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"
    }
  ]
}