CVE-2026-46671

File-existence probing via unchecked notebook entry paths

Published Jul 20, 2026 · Updated Jul 20, 2026

Path traversal in onenote_parser before 1.1.1 allows attackers to probe files or interrupt service through a crafted .onetoc2 file. Parser::parse_notebook joins untrusted table-of-contents entry names to the notebook base directory without rejecting absolute or parent paths, then opens the resolved files. Exploitation requires a consuming application to parse an attacker-supplied notebook; invalid sections block direct content return, while large or special targets can hang or crash the process and path outcomes reveal file existence.

CVSS severity4.4
Medium
EPSS probability0.19%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Path traversal in onenote_parser before 1.1.1 allows attackers to probe files or interrupt service through a crafted .onetoc2 file. Parser::parse_notebook joins untrusted table-of-contents entry names to the notebook base directory without rejecting absolute or parent paths, then opens the resolved files. Exploitation requires a consuming application to parse an attacker-supplied notebook; invalid sections block direct content return, while large or special targets can hang or crash the process and path outcomes reveal file existence.

The record

CVE
CVE-2026-46671
Published
Jul 20, 2026
Updated
Jul 20, 2026
Vendor
Markus Siemens
Product
onenote_parser
Classifications
CWE-22, T1499.004
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 20, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 20, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 1.1.1

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Markus Siemens · onenote_parserversion=< 1.1.1

Published CVSS scores

4.4GitHubCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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