notepad-plus-plus: Path Equivalence: 'filename.' (Trailing Dot)
CVE-2026-52884 is a high-severity path equivalence: 'filename.' (trailing dot) vulnerability in notepad-plus-plus, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. Affected notepad-plus-plus versions: = 8.9.6.1. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.21% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of notepad-plus-plus you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on github.com for workarounds and exact fixed builds.
- Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Notepad-plus-plus | notepad-plus-plus | = 8.9.6.1 | Not stated |
| Notepad-plus-plus | Notepad++ | 8.9.6.1 | Not 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
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- RequiredA user must take an action such as opening a file or link.
- 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:L/PR:N/UI:R/S:U/C:H/I:H/A:H. Scored by CNA (github.com).
Official description
Notepad++ is a free and open-source source code editor. In v8.9.6.1, isInTrustedDirectory() does NOT canonicalize the path before checking. It uses a prefix-based check (PathIsPrefix() or equivalent) that matches paths starting with trusted directory strings. A path traversal using ..\..\ after a trusted directory prefix passes the check while resolving to an untrusted location. The CVE-2026-48800 patch adds isInTrustedDirectory() validation in Command::run() (RunDlg.cpp) before calling ShellExecute(). This function checks whether the resolved executable path is under a trusted directory. This vulnerability is fixed in 8.9.6.2.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Path Equivalence: 'filename.' (Trailing Dot)
The product accepts path input in the form of trailing dot ('filedir.') without appropriate validation, which can lead to ambiguous path resolution and allow an attacker to traverse the file system to unintended locations or access arbitrary files.
More Path Equivalence: 'filename.' (Trailing Dot) vulnerabilities (CWE-42)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Advisories
Patches and release notes
Other vulnerabilities in notepad-plus-plus
- 7.8 High severity
- 7.3 High severity
- 8.6 High severity
- 7.8 High severity
- 8.1 High severity
- 7.8 High severity
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