Is CVE-2026-48770 being exploited?

No public exploit is currently tracked.

How severe is CVE-2026-48770?

CVE-2026-48770 has a CVSS v3 severity of MEDIUM (5).

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CVE-2026-48770

Description

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.