{"id":"GHSA-gcmj-c9gg-9vh6","summary":"@joplin/onenote-converter: Path traversal in OneNote importer allows overwriting arbitrary files","details":"### Summary\nA path traversal vulnerability in the OneNote importer allows overwriting arbitrary files on disk.\n\n### Details\nThe OneNote converter does not sanitize the names of embedded files before writing them to disk. As a result, it's possible for an attacker to create a malicious `.one` file that includes file names containing `../../`, that are then interpreted as part of the target path when extracting attachments from the `.one` file.\n\nOne affected location is `embedded_file.rs`, which generates a file name from a string previously parsed from the `.one` file,\nhttps://github.com/laurent22/joplin/blob/af5108d70233b1db9410346958c1587cf7c1b16d/packages/onenote-converter/renderer/src/page/embedded_file.rs#L13-L16\n\nAbove, [`determine_filename`](https://github.com/laurent22/joplin/blob/af5108d70233b1db9410346958c1587cf7c1b16d/packages/onenote-converter/renderer/src/page/embedded_file.rs#L56-L64) passes through the provided file name.\n\n[Similar logic](https://github.com/laurent22/joplin/blob/4d7fa5972fe2986eae14cbf3a2801835cbe1384e/packages/onenote-converter/src/page/embedded_file.rs#L14) has been present since 4d7fa5972fe2986eae14cbf3a2801835cbe1384e (Joplin 3.2.2), when the OneNote importer was first introduced.\n\n### PoC\n\n[Screencast from 2025-11-20 13-50-21.webm](https://github.com/user-attachments/assets/a9d6cc64-ec11-4f33-9f92-32efe0eaab23)\n\n\n1. Import [poc_v2.zip](https://github.com/user-attachments/files/23664109/poc_v2.zip).\n2. Open the application's profile directory, then open `log.txt`.\n3. Observe that `log.txt` has been overwritten non-log-file content (a WAV file).\n\nTested on Fedora Linux 43 with Joplin 3.4.12 (prod, linux) and Joplin 3.5.6 (dev, linux).\n\n**Note**: The PoC ZIP file overwrites Joplin's `log.txt`. It is also possible to craft a file that overwrites more sensitive system files (e.g. `.bashrc` on Linux).\n\n### Impact\nThis is a path traversal vulnerability that impacts **all versions of Joplin (\u003c= v3.5.6) that include a OneNote importer**. Importing a crafted OneNote export file allows an attacker to overwrite arbitrary files, potentially leading to remote code execution.\n\n### Patched in\n\n- **Joplin**: https://github.com/laurent22/joplin/commit/791668455e1aae50501ff57ea4783b3fba9d377c\n- **one2html**: https://github.com/msiemens/one2html/commit/948d65cdca5bb35d776b8b235ec05ff15249fd41","aliases":["CVE-2026-22810"],"modified":"2026-09-10T03:51:05.689991880Z","published":"2026-05-15T16:27:11Z","database_specific":{"cwe_ids":["CWE-24"],"severity":"HIGH","github_reviewed":true,"github_reviewed_at":"2026-05-15T16:27:11Z","nvd_published_at":"2026-05-18T21:16:39Z"},"references":[{"type":"WEB","url":"https://github.com/laurent22/joplin/security/advisories/GHSA-gcmj-c9gg-9vh6"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-22810"},{"type":"WEB","url":"https://github.com/laurent22/joplin/pull/13736"},{"type":"WEB","url":"https://github.com/laurent22/joplin/commit/791668455e1aae50501ff57ea4783b3fba9d377c"},{"type":"PACKAGE","url":"https://github.com/laurent22/joplin"},{"type":"WEB","url":"https://github.com/laurent22/joplin/blob/af5108d70233b1db9410346958c1587cf7c1b16d/packages/onenote-converter/renderer/src/page/embedded_file.rs#L13-L16"},{"type":"WEB","url":"https://github.com/laurent22/joplin/releases/tag/v3.5.7"}],"affected":[{"package":{"name":"@joplin/onenote-converter","ecosystem":"npm","purl":"pkg:npm/%40joplin/onenote-converter"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"3.5.7"}]}],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/05/GHSA-gcmj-c9gg-9vh6/GHSA-gcmj-c9gg-9vh6.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H"}]}