CVE-2025-15556

HIGH CISA KEV

CVSS v3

7.5

HIGH

EPSS Score

4.3%

exploit probability

CISA KEV

Yes

known exploited

Exploitation

SSVC status

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
2/12/2026
Patch Due Date
3/5/2026
Required Action
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Technical Details

CVSS v3 Vector
3.1
Published
2/3/2026
Last Modified
2/13/2026

Frequently Asked Questions

What is 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.

Is CVE-2025-15556 actively exploited?

Yes. CVE-2025-15556 is on the CISA Known Exploited Vulnerabilities (KEV) catalog, meaning it has been confirmed as actively exploited in the wild. CISA requires federal agencies to patch by 3/5/2026.

What is the CVSS score for CVE-2025-15556?

CVE-2025-15556 has a CVSS v3 base score of 7.5 (HIGH severity), with vector string 3.1.

Is CVE-2025-15556 affecting your environment?

Use isMalicious to check if any of your IPs or domains are associated with this vulnerability's IOCs.