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.
ACTIVELY EXPLOITED IN THE WILD
This vulnerability is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
Notepad++ Download of Code Without Integrity Check Vulnerability
Notepad++ Notepad++
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
2/12/2026
https://notepad-plus-plus.org/news/clarification-security-incident/ ; https://community.notepad-plus-plus.org/topic/27298/notepad-v8-8-9-vulnerability-fix ; https://nvd.nist.gov/vuln/detail/CVE-2025-15556
Vulnerability Summary
CVSS v3 Score
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS Score (Exploitation Probability)
This vulnerability has a 6.09% probability of being exploited in the next 30 days, ranking higher than 91% of all scored CVEs.
CWE Classification
Related Vulnerabilities
Same Weakness Type(CWE-494)
TrueConf Client downloads application update code and applies it without performing verification. An attacker who is able to influence the update delivery path can substitute a tampered update payload. If the payload is executed or installed by the updater, this may result in arbitrary code execution in the context of the updating process or user.
pnpm is a package manager. Versions 10.26.2 and below store HTTP tarball dependencies (and git-hosted tarballs) in the lockfile without integrity hashes. This allows the remote server to serve different content on each install, even when a lockfile is committed. An attacker who publishes a package with an HTTP tarball dependency can serve different code to different users or CI/CD environments. The attack requires the victim to install a package that has an HTTP/git tarball in its dependency tree. The victim's lockfile provides no protection. This issue is fixed in version 10.26.0.
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Vasion Print (formerly PrinterLogic) Virtual Appliance Host prior to version 22.0.843 and Application prior to version 20.0.1923 (VA/SaaS deployments) possess CI/CD weaknesses: the build pulls an unverified third-party image, downloads the VirtualBox Extension Pack over plain HTTP without signature validation, and grants the jenkins account NOPASSWD for mount/umount. Together these allow supply chain or man-in-the-middle compromise of the build pipeline, injection of malicious firmware, and remote code execution as root on the CI host. This vulnerability has been identified by the vendor as: V-2023-007 — Supply Chain Attack.
Certain General Electric Renewable Energy products download firmware without an integrity check. This affects iNET and iNET II before 8.3.0, SD before 6.4.7, TD220X before 2.0.16, and TD220MAX before 1.2.6.
Similar SeverityHIGH
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