CVE-2026-48770
Notepad++ WM_COPYDATA COPYDATA_FULL_CMDLINE local DoS crash
MEDIUM 5.0EPSS 0.1%
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.
- Affected
- notepad-plus-plus
- CVSS v3.1 GITHUB
- 5.0 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H - EPSS
- 0.14% chance of exploitation in the next 30 days, 3rd percentile
- Published
- 2026-06-26
- Updated
- 2026-06-29
Proof-of-concept exploits (1)
- atiilla/Notepad-8.9.6-PoC6★ · 2026-05-28
Security advisories
- notepad-plus-plus/notepad-plus-plus/security/advisories/GHSA-r39g-3mcw-xcg2
- notepad-plus-plus/notepad-plus-plus/commit/f20a0888a92ce557a339b833cd9d9d8e97dc797d