CyberSecBulletin
CVE-2026-4546NVD status: Analyzed

Notepad2: Untrusted Search Path

CVE-2026-4546 is a high-severity untrusted search path vulnerability in Notepad2 from Flos Freeware, with a CVSS 3.1 base score of 7.0 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. Affected Notepad2 versions: 4.2.25. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.22% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of Notepad2 you run against the affected versions below, and install the vendor's latest release.

Affected products and versions

VendorProductAffected versionsFixed in
Flos FreewareNotepad24.2.25Not stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
HighSuccess depends on conditions outside the attacker's control.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (vuldb.com).

Scoring systemScoreSeverityScored by
CVSS 4.07.3HighCNA (vuldb.com)
CVSS 3.17.0HighCNA (vuldb.com)
CVSS 2.06.0MediumCNA (vuldb.com)

Official description

A weakness has been identified in Flos Freeware Notepad2 4.2.25. This impacts an unknown function in the library TextShaping.dll. Executing a manipulation can lead to uncontrolled search path. The attack is restricted to local execution. The attack requires a high level of complexity. The exploitability is said to be difficult. The vendor was contacted early about this disclosure but did not respond in any way.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Untrusted Search Path

The product searches for critical resources using an externally-supplied search path that can point to resources that are not under the product's direct control.

How developers prevent this class of flaw

  • Hard-code the search path to a set of known-safe values (such as system directories), or only allow them to be specified by the administrator in a configuration file. Do not allow these settings to be modified by an external party. Be careful to avoid related weaknesses such as CWE-426 and CWE-428.
  • When invoking other programs, specify those programs using fully-qualified pathnames. While this is an effective approach, code that uses fully-qualified pathnames might not be portable to other systems that do not use the same pathnames. The portability can be improved by locating the full-qualified paths in a centralized, easily-modifiable location within the source code, and having the code refer to these paths.
  • Remove or restrict all environment settings before invoking other programs. This includes the PATH environment variable, LD_LIBRARY_PATH, and other settings that identify the location of code libraries, and any application-specific search paths.

More Untrusted Search Path vulnerabilities (CWE-426)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Technical write-ups (may include proof of concept)

Other vulnerabilities in Notepad2

All Notepad2 vulnerabilities

Recent Untrusted Search Path vulnerabilities

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