Notepad++ < 8.8.9 WinGUp Updater Lacks Update Integrity Verification
Affects Notepad++ versions before 8.8.9 that use the WinGUp updater. Fixed in 8.8.9, which verifies the certificate and signature of downloaded installers.
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Listed in CISA KEV
- How many real-world setups can hit the bug, from the vendor's advisory and CISA data. It does not know your setup.What do these mean? →
- Actively exploited
- Fix
- Fixed in 8.8.9
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
Notepad++ versions before 8.8.9 are affected when they use the WinGUp updater. An attacker who can intercept or redirect update traffic could trick the updater into running a malicious installer, allowing arbitrary code to run with the user's privileges.
Summarized by anthropic/claude-haiku-5.5. Verify details against the original sources.
Read the original 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.
Timeline
- CVE published
- Added to CISA KEV
CISA has evidence of exploitation in the wild
- Record last updated
- CISA remediation deadline
Due date for US federal agencies to patch
Affected versions
- notepad-plus-plus notepad-plus-plus
fixed in 8.8.9
References 5
community.notepad-plus-plus.org
notepad-plus-plus.org
GitHub · notepad-plus-plus/notepad-plus-plus
GitHub · notepad-plus-plus/wingup
Questions about CVE-2025-15556
What does this mean?
The WinGUp updater did not verify the certificate or signature of downloaded installers. An attacker who could intercept and redirect update traffic for notepad-plus-plus.org could direct the updater to attacker-controlled update manifests and supply their own updates.Source: notepad-plus-plus.org
Am I affected, and how do I check?
Notepad++ versions before 8.8.9 that use the WinGUp updater. The attacker condition is the ability to intercept and redirect update traffic for notepad-plus-plus.org.Source: notepad-plus-plus.org
What should I do about it?
Upgrade Notepad++ to 8.8.9 or later, which adds certificate and signature verification to WinGUp.Source: notepad-plus-plus.org
Is it being exploited?
Yes. CISA added it to its Known Exploited Vulnerabilities catalog on 2026-02-12, which means it has evidence of attacks. No public exploit code is tracked.Source: cisa.gov, cve.now feed data