GHSA-4j5m-wc25-pvh7 is a medium-severity (CVSS 4.4) Path Traversal vulnerability in onenote_parser. O3 Security confirms whether GHSA-4j5m-wc25-pvh7 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Rust OneNote File Parser: Path traversal in `Parser::parse_notebook` allows reading files outside the notebook directory
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-4j5m-wc25-pvh7.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
GHSA-4j5m-wc25-pvh7 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 360,781 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
onenote_parserReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects crates.io packages — download data is not available via public APIs for these ecosystems.
Description
Impact
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.
Patches
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.
Workarounds
For users who cannot upgrade to 1.1.1:
- Only call
Parser::parse_notebookon.onetoc2files from trusted sources. - Alternatively, use
Parser::parse_section/Parser::parse_section_bufferon individual .one files, which do not perform the directory walk.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | onenote_parser | all versions | 1.1.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for onenote_parser. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update onenote_parser to 1.1.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-4j5m-wc25-pvh7 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-4j5m-wc25-pvh7 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-4j5m-wc25-pvh7. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-4j5m-wc25-pvh7 in your dependencies?
O3 detects GHSA-4j5m-wc25-pvh7 across crates.io dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.