CVE-2025-15556

Notepad++ < 8.8.9 WinGUp Updater Lacks Update Integrity Verification

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.

Affected

notepad-plus-plus

CVSS v4.0 VULNCHECK

7.7 HIGHCVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

CVSS v3.1 NVD

7.5 HIGHCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H

EPSS

1.77% chance of exploitation in the next 30 days, 78th percentile

CISA KEV

added 2026-02-12

Published

2026-02-03

Updated

2026-03-05

Proof-of-concept exploits (1)

• George0Papasotiriou/CVE-2025-15556-Notepad-WinGUp-Updater-RCE1★ · 2026-02-10

Security advisories

• https://notepad-plus-plus.org//news//clarification-security-incident
• https://notepad-plus-plus.org/news/hijacked-incident-info-update
• https://www.vulncheck.com/advisories/notepad-plus-plus-wingup-updater-lacks-update-integr…
• notepad-plus-plus/notepad-plus-plus/commit/bcf2aa68ef414338d717e20e059459570ed6c5ab
• notepad-plus-plus/wingup/commit/ce0037549995ed0396cc363544d14b3425614fdb
• https://community.notepad-plus-plus.org/topic/27298/notepad-v8-8-9-vulnerability-fix

References

• CVE Record
• NVD entry