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TI-2026-36040 Aliases CVE-2026-48770

Notepad++ WM_COPYDATA COPYDATA_FULL_CMDLINE local DoS crash

Priority MEDIUM 56CWE-125Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
Required
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-125 and the CVSS impact.

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00142 3rd percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed notepad-plus-plus (notepad-plus-plus): 8.9.6.1

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
notepad-plus-plusnotepad-plus-plusbefore 8.9.6.18.9.6.1Patch availableCNA
  • notepad-plus-plus Vendornotepad-plus-plus Affected before 8.9.6.1 Fixed in 8.9.6.1 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:notepad-plus-plus:notepad\+\+:*:*:*:*:*:*:*:*before 8.9.6.1Vulnerablenotepad-plus-plus
  • cpe:2.3:a:notepad-plus-plus:notepad\+\+:*:*:*:*:*:*:*:* Versions before 8.9.6.1 Vulnerable ·notepad-plus-plus

Remediation

  • Fix · CNA notepad-plus-plus (notepad-plus-plus) Fixed in 8.9.6.1

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-48770

References

Exploit 1

Patch 1

  • TI-2025-14195 Notepad++ < 8.8.9 WinGUp Updater Lacks Update Integrity Verification KEVCVSS 4.0HIGH 7.7
  • TI-2026-36070 Notepad++: Arbitrary Code Execution via shortcuts.xml UserCommand Injection CVSS 3.1HIGH 7.8
  • TI-2026-36048 Notepad++: Arbitrary Code Execution via config.xml commandLineInterpreter CVSS 3.1HIGH 7.8
  • TI-2026-04836 Stack-Based Buffer Overflow in Notepad++ File Drop Handler leads to DoS CVSS 3.1HIGH 7.8
  • TI-2023-20921 Notepad++ vulnerable to heap buffer write overflow in Utf8_16_Read::convert CVSS 3.1HIGH 7.8
  • TI-2026-37981 Notepad++ TOCTOU: HMAC Checks Disk, Executes from Memory CVSS 4.0HIGH 7.5
See all 19 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences