- High 7.7
- Known exploited (CISA KEV)
CVE-2025-15556
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.
Scores
The facts
- Published
- 3 February 2026
- Last changed
- 17 June 2026
- NVD status
- Analyzed
- Severity
- High, CVSS 7.7 out of 10 (version 4.0)
CVSS: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… - Weakness
- Affects
- notepad-plus-plus notepad++
- Known exploited
- Yes. CISA added it to the Known Exploited Vulnerabilities catalogue on 12 February 2026.
- EPSS
- 1.8% chance of exploitation activity in the next 30 days (percentile 78).
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References
- github.com/…/bcf2aa68ef414338d717e20e059459570ed6c5ab
- github.com/…/ce0037549995ed0396cc363544d14b3425614fdb
- notepad-plus-plus.org/news/hijacked-incident-info-update
- notepad-plus-plus.org/news/clarification-security-incident
- community.notepad-plus-plus.org/…/notepad-v8-8-9-vulnerability-fix
- CVE-2025-15556 in the NVD