CVE-2026-46671Rust OneNote File Parser: Path traversal in `Parser::parse_notebook` allows reading files outside the notebook directory
- 4.4MediumCVSS base score
- 0.15%Exploitation in 30 daysEPSS · top 96% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
Rust OneNote File Parser is a parser for Microsoft OneNote files implemented in Rust. Prior to version 1.1.1, a maliciously crafted `.onetoc2` table-of-contents file can cause `Parser::parse_notebook` to open arbitrary files on the host filesystem outside the notebook's directory. The parser reads entry names listed inside the `.onetoc2` and joins them against the notebook's base directory without validating that they are relative paths confined to that directory. The parser will bail out when the target file fails to parse as a OneNote section, so direct content exfiltration through the parser's return value is not practical, though file-existence probing and denial-of-service via large or special files remain possible. Anyone using `onenote_parser` to parse .onetoc2 files received from untrusted sources is affected. Users who only ever parse their own notebooks are not at meaningful risk. The issue is fixed in onenote_parser 1.1.1. The fix rejects absolute paths, parent-directory components, and other invalid path characters in entry names, and additionally canonicalises the resolved path to confirm it stays inside the notebook's base directory. For users who cannot upgrade to 1.1.1, only call `Parser::parse_notebook` on `.onetoc2` files from trusted sources. Alternatively, use `Parser::parse_section` / `Parser::parse_section_buffer` on individual .one files, which do not perform the directory walk.
Timeline
ID reserved
By GitHub_M
- 2 months later
· 2 months later
Published
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | Medium4.4 | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:L |
| NVDNVD · Analyzed | 3.1 | Medium4.4 | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:L |
- EPSS (exploitation in 30 days)
- 0.15% · top 96% of all CVEs (14 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 4.4.
Affected products
- affected < 1.1.1
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- crates.ioonenote_parserGHSA-4j5m-wc25-pvh7 (opens in a new tab)
References
References4
- https://github.com/msiemens/onenote.rs/security/advisories/GHSA-4j5m-wc25-pvh7 (opens in a new tab)x_refsource_CONFIRM
- https://github.com/msiemens/onenote.rs/commit/c9267b2c96e2542be7e7b557d67318e81b733585 (opens in a new tab)x_refsource_MISC
- https://github.com/msiemens/onenote.rs/blob/master/CHANGELOG.md#111---2026-05-15 (opens in a new tab)x_refsource_MISC
- https://github.com/msiemens/onenote.rs/releases/tag/v1.1.1 (opens in a new tab)x_refsource_MISC
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-45987 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-4j5m-wc25-pvh7 (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-46671)Record last updated .