CVE-2025-15556
HighExploitedPublic exploitNotepad++ 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.
Published Feb 2, 2026 · Updated Aug 12, 2026
Key Facts
Patch immediately- CVE-2025-15556 is a high-severity vulnerability (CVSS 7.7 v4) affecting Notepad\+\+ (Notepad-Plus-Plus), notepad-plus-plus.
- It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Feb 2, 2026. Public exploit code is available.
- EPSS estimates a 1.8% probability of exploitation in the next 30 days.
- Fixed versions are available, including notepad-plus-plus 8.8.9, Notepad\+\+ 8.8.9.
- Brandefense priority: patch immediately, because it is listed as exploited in the wild.
CVSS v4
7.7
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:X/V:X/RE:X/U:X
EPSS (30-day exploit likelihood)
1.8%
Higher than 77.7% of all scored CVEs
Exploited in the wild
Yes
4 catalog listings
Public exploit code
Available
Proof-of-concept or weaponized module
Get the full CVE-2025-15556 brief as a PDF
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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.
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| CISA KEV | Feb 12, 2026 | Mar 5, 2026 | Not reported |
| Industry KEV feed | Feb 2, 2026 | Mar 5, 2026 | Not reported |
| CIRCL KEV | Feb 12, 2026 | Mar 5, 2026 | Not reported |
| ENISA EUVD | Feb 12, 2026 | n/a | Not reported |
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.
Affected Products
2 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| Notepad\+\+Notepad-Plus-Plus | See advisory | 8.8.9 |
| notepad-plus-plus | See advisory | 8.8.9 |
Patched Releases
notepad-plus-plus
8.8.9
Notepad\+\+
8.8.9
Timeline
Publicly disclosed
Feb 2, 2026
Added to Industry KEV feed
Feb 2, 2026
Added to CISA KEV
Feb 12, 2026
Added to CIRCL KEV
Feb 12, 2026
Added to ENISA EUVD
Feb 12, 2026
Last updated
Aug 12, 2026
Weakness Type
- CWE-494 Download of Code Without Integrity Check
References
- advisoryhttps://github.com/CVEProject/cvelistV5/tree/main/cves/2025/15xxx/CVE-2025-15556.json
- advisoryhttps://notepad-plus-plus.org//news//clarification-security-incident/
- advisoryhttps://nvd.nist.gov/vuln/detail/CVE-2025-15556
- advisoryhttps://www.vulncheck.com/advisories/notepad-plus-plus-wingup-updater-lacks-update-integrity-verification
- patchhttps://github.com/notepad-plus-plus/notepad-plus-plus/commit/bcf2aa68ef414338d717e20e059459570ed6c5ab
FAQ
Common Questions.
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.
Affected: Notepad\+\+ (Notepad-Plus-Plus); notepad-plus-plus. The full list is in the CVE brief.
It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Feb 2, 2026.
Yes. It was added on Feb 12, 2026 with a federal remediation due date of Mar 5, 2026.
Public exploit code is available.
Fixed versions are available, including notepad-plus-plus 8.8.9, Notepad\+\+ 8.8.9.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
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