{"id":"GHSA-v9p7-gf3q-h779","summary":"@tinacms/graphql has Path Traversal that leads to overwrite of arbitrary files","details":"### Summary\nA Path Traversal vulnerability in `@tinacms/graphql` allows unauthenticated users to write and overwrite arbitrary files within the project root. This is achieved by manipulating the `relativePath` parameter in GraphQL mutations. The impact includes the ability to replace critical server configuration files and potentially execute arbitrary commands by sabotaging build scripts.\n\n### Details\nThe vulnerability exists in the path validation logic within `@tinacms/graphql`. Specifically, the regex-based validation in `getValidatedPath` fails to recognize backslashes (`\\`) as directory separators on non-Windows platforms (Mac/Linux). An attacker can provide a path like `x\\..\\..\\..\\package.json`, which bypasses the validation check but is subsequently treated as a traversal path during file I/O operations by the underlying `fs` modules and path normalization utilities.\n\nIncriminated code areas:\n- [packages/@tinacms/graphql/src/database/bridge/filesystem.ts](tinacms/packages/@tinacms/graphql/src/database/bridge/filesystem.ts): [assertWithinBase](tinacms/graphql/src/database/bridge/filesystem.ts#7-35) function.\n- [packages/@tinacms/graphql/src/resolver/index.ts](tinacms/packages/@tinacms/graphql/src/resolver/index.ts): `getValidatedPath` function.\n\n### PoC\n1. Start the TinaCMS development server.\n2. Send a malicious GraphQL mutation to overwrite a project file (e.g., [package.json](tinacms/examples/tina-self-hosted-demo/package.json)):\n\n```bash\ncurl -X POST http://localhost:4001/graphql \\\n  -H \"Content-Type: application/json\" \\\n  -d '{\"query\": \"mutation { updateDocument(collection: \\\"global\\\", relativePath: \\\"x\\\\\\\\..\\\\\\\\..\\\\\\\\..\\\\\\\\package.json\\\", params: { global: { header: { name: \\\"OVERWRITTEN\\\" } } }) { __typename } }\"}'\n```\n\n3. Observe that the root [package.json](tinacms/examples/tina-self-hosted-demo/package.json) has been replaced with the provided payload.\n\n\u003cimg width=\"1424\" height=\"516\" alt=\"2026-03-15_12-24-05 PM\" src=\"https://github.com/user-attachments/assets/9fdf94ce-2183-4a24-9cd9-48f21deb9768\" /\u003e\n\n\u003cimg width=\"1387\" height=\"774\" alt=\"2026-03-15_12-27-33 PM\" src=\"https://github.com/user-attachments/assets/676f083b-f934-4cf2-978b-bb2fabee0216\" /\u003e\n\n### Impact\nThis is an **Arbitrary File Write** vulnerability. Any unauthenticated user with network access to the GraphQL API can:\n- Overwrite critical server configuration files (e.g., [package.json](tinacms/examples/tina-self-hosted-demo/package.json), [tsconfig.json](tinacms/examples/tina-self-hosted-demo/tsconfig.json)).\n- Host malicious scripts in the `public/` directory for client-side attacks.\n- Perform **Arbitrary Code Execution** by modifying build scripts or server-side logic files that are subsequently executed by the environment.\n\n\n\n**Weaknesses:**\n- **CWE-22**: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')\n- **CWE-73**: External Control of File Name or Path","aliases":["CVE-2026-33949"],"modified":"2026-04-06T17:04:33.962142Z","published":"2026-03-30T17:07:53Z","database_specific":{"github_reviewed_at":"2026-03-30T17:07:53Z","nvd_published_at":"2026-04-01T17:28:39Z","cwe_ids":["CWE-22","CWE-73"],"severity":"HIGH","github_reviewed":true},"references":[{"type":"WEB","url":"https://github.com/tinacms/tinacms/security/advisories/GHSA-v9p7-gf3q-h779"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-33949"},{"type":"PACKAGE","url":"https://github.com/tinacms/tinacms"}],"affected":[{"package":{"name":"@tinacms/graphql","ecosystem":"npm","purl":"pkg:npm/%40tinacms/graphql"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"2.2.2"}]}],"database_specific":{"last_known_affected_version_range":"\u003c= 2.2.1","source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/03/GHSA-v9p7-gf3q-h779/GHSA-v9p7-gf3q-h779.json"}}],"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:H/A:H"}]}