Vulnerability Details CVE-2026-48770
Notepad++ is a free and open-source source code editor. Prior to 8.9.6.1, a local process in the same interactive Windows session can send a malformed WM_COPYDATA message to Notepad++ using the COPYDATA_FULL_CMDLINE path. The handler appears to process COPYDATASTRUCT.lpData as an unbounded NUL-terminated wchar_t* instead of enforcing COPYDATASTRUCT.cbData. This vulnerability is fixed in 8.9.6.1.
Exploit prediction scoring system (EPSS) score
EPSS Score 0.003
EPSS Ranking 18.6%
CVSS Severity
CVSS v3 Score 5.0