CVE-2026-46671

Rust OneNote File Parser: Path traversal in `Parser::parse_notebook` allows reading files outside the notebook directory

Published Jul 20, 2026 CVSS 3.1 · 4.4 Medium EPSS < 1% KEV · Not listed
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-4j5m-wc25-pvh7 Rust OneNote File Parser: Path traversal in `Parser::parse_notebook` allows reading files outside the notebook directory
History
Type Values Removed Values Added
First Time appeared Msiemens rust Onenote File Parser
CPEs cpe:2.3:a:msiemens:rust_onenote_file_parser:*:*:*:*:*:rust:*:*
Vendors & Products Msiemens rust Onenote File Parser
Type Values Removed Values Added
First Time appeared Msiemens
Msiemens onenote.rs
Vendors & Products Msiemens
Msiemens onenote.rs
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
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.
Title Rust OneNote File Parser: Path traversal in `Parser::parse_notebook` allows reading files outside the notebook directory
Weaknesses CWE-22
References
Metrics cvssV3_1

{'score': 4.4, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:L'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Jul 20, 2026, 5:31 PM
Reserved
May 15, 2026, 9:46 PM
Status
Analyzed
Published
Jul 20, 2026, 4:17 PM
Modified
Oct 24, 2026, 8:10 PM