CVE-2025-15556
Published: February 12, 2026
Official Description
Notepad++ when using the WinGUp updater, contains a download of code without integrity check vulnerability that could allow an attacker to intercept or redirect update traffic to download and execute an attacker-controlled installer. This could lead to arbitrary code execution with the privileges of the user.
CISA KEV Advisory
Notepad++ Download of Code Without Integrity Check Vulnerability
Notepad++ when using the WinGUp updater, contains a download of code without integrity check vulnerability that could allow an attacker to intercept or redirect update traffic to download and execute an attacker-controlled installer. This could lead to arbitrary code execution with the privileges of the user.
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Risk Analysis
This high-severity vulnerability in Notepad++'s WinGUp updater allows an attacker to intercept or redirect update traffic, leading to arbitrary code execution. With a CVSS score of 7.5, it is a significant risk. Despite a low EPSS score of 0.02693, its presence in CISA's KEV catalog confirms active exploitation.
This vulnerability is actively exploited in the wild and is listed in CISA's KEV catalog. It is remotely exploitable, requiring user interaction to download and execute an attacker-controlled installer.
Update Notepad++ to a version that uses a secure updater. Ensure that all software updates are downloaded from trusted sources and verified for integrity.
Technical Analysis
CVE-2025-15556 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
Exploitation does not require any privileges, though user interaction (Required) is needed, which slightly reduces the risk of mass automated attacks.
A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 7.5.
CISA has added CVE-2025-15556 to the Known Exploited Vulnerabilities (KEV) catalog, confirming active exploitation in the wild. U.S. federal agencies are required to patch this within the mandated timeframe, and all organizations should treat remediation as urgent.
CVSS v3.1 Vector Breakdown
Exploit & PoC Resources
News & Research Mentioning CVE-2025-15556
CISA has added four new vulnerabilities to its Known Exploited Vulnerabilities (KEV) Catalog, based on evidence of active exploitation. CVE-2024-43468 Microsoft Configuration Manager SQL Injection Vulnerability CVE-2025-15556 Notepad++ Download of Code Without Integrity Check Vulnerability CVE-2025-40536 SolarWinds Web Help Desk Security Control Bypass Vulnerability CVE-2026-20700 Apple Multiple Buffer Overflow Vulnerability These types of vulnerabilities are frequent attack vectors for malicious cyber actors and pose significant risks to the federal enterprise. Binding Operational Directive (BOD) 22-01: Reducing the Significant Risk of Known Exploited Vulnerabilities established the KEV Catalog as a living list of known Common Vulnerabilities and Ex [xlite_meta score:47 src:CISA Alerts xlite_fp:098a19bd7fa4d5615695022f72e740127ed9fc369ea6e6a0fc9f3b03774191fd]
All References (3)
Quick Facts
Known Threat Actors
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2025-15556 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts
- !CISA KEV: Federal agencies must patch per BOD 22-01 timeline
- !Active exploitation confirmed — treat as P1