# CVE-2026-52886: Notepad++: session.xml backupFilePath starts_with Bypass

CVE-2026-52886 is fixed in Notepad++ on 1 platform by Notepad++ 8.9.7 (version 8.9.7), released July 14, 2026. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2026-52886
- Priority: Routine
- CVSS: 5.1
- EPSS: 0.0017
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Aug 17, 2026
- Weakness: CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
- Vendor advisory: https://nvd.nist.gov/vuln/detail/CVE-2026-52886

## Description

Notepad++ is a free and open-source source code editor. Prior to 8.9.7, Notepad++ validates the backupFilePath attribute from session.xml with std::wstring::starts_with against the expected backup directory without path normalization, allowing parent-directory sequences during snapshot-mode restoration to read an arbitrary user-readable file outside the backup directory into an editor tab. This issue is fixed in version 8.9.7.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Windows apps | Notepad++ | 8.9.7 | [Notepad++ 8.9.7](https://patchblox.com/security/data/fix/windows-app/notepad-.notepad-8.9.7.md) | Jul 14, 2026 |

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Data as of 2026-11-08T00:53:09Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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