Description
Notepad++ versions prior to 8.8.9, when using the WinGUp updater, contain an update integrity verification vulnerability where downloaded update metadata and installers are not cryptographically verified. An attacker able to intercept or redirect update traffic can cause the updater to download and execute an attacker-controlled installer, resulting in arbitrary code execution with the privileges of the user.
CISA Known Exploited Vulnerability
Date added 2026-02-12 | Due date 2026-03-05
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Problem types
CWE-494 Download of Code Without Integrity Check
Product status
Any version before 8.8.9
Timeline
| 2025-12-09: | Vulnerability is publicly disclosed |
| 2026-02-02: | Announcement of exploitation in the wild |
References
www.cisa.gov/...erabilities-catalog?field_cve=CVE-2025-15556
notepad-plus-plus.org/...s//clarification-security-incident/
community.notepad-plus-plus.org/...-v8-8-9-vulnerability-fix
notepad-plus-plus.org/news/hijacked-incident-info-update/
github.com/...ommit/bcf2aa68ef414338d717e20e059459570ed6c5ab
github.com/...ommit/ce0037549995ed0396cc363544d14b3425614fdb
www.vulncheck.com/...ter-lacks-update-integrity-verification