CVE-2026-48770 json
Notepad++ WM_COPYDATA COPYDATA_FULL_CMDLINE local DoS crash
published 2026-06-26 4 mo ago modified 2026-06-29 4 mo ago also EUVD-2026-39908
- cvss
- 5.0
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.1%
- EPSS 0.1% chance of exploitation in 30 days, percentile 3%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- notepad-plus-plus notepad++ 8.9.6.1
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- partial
- Assessed
- 4 mo ago
Exploit prediction
0.14% chance of exploitation in the next 30 days, higher than 3% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/notepad-plus-plus/notepad-plus-plus/security/advisories/GHSA-r39g-3mcw-xcg2 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 5.0 | CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H |
Affected products
- notepad-plus-plus notepad-plus-plus
Classification
- Weakness
-
- CWE-125 Out-of-bounds Read
References
-
github.com
/notepad-plus-plus/notepad-plus-plus/commit/f20a0888a92ce557a339b833cd9d9d8e97dc797d
patch
-
github.com
/notepad-plus-plus/notepad-plus-plus/security/advisories/GHSA-r39g-3mcw-xcg2
exploit, patch, vendor-advisory, mitigation
Sources
- CVE List CVE-2026-48770
- NVD CVE-2026-48770
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.