Path Traversal in Notepad-Plus-Plus

CVE-2026-57233

Notepad++ is a free and open-source source code editor. Prior to 8.9.7, the WinGup decompress function joins untrusted ZIP entry names to unzipDestTo without canonical containment validation, allowing an entry such as ../mimeTools/mimeTools.dll to overwrite a DLL in a sibling plugin directory and execute attacker-controlled code when Notepad++ next loads that plugin. This issue is fixed in version 8.9.7.

Vulnerability class: Path Traversal (Directory Traversal)

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-57233?
CVE-2026-57233 is a high-severity vulnerability in Notepad-Plus-Plus, classified under Path Traversal. CVSS score: 8.1/10. Published 2026-08-17.
How severe is CVE-2026-57233?
High severity. CVSS v3 base score is 8.1 out of 10.