CVE-2026-86056 (GCVE-0-2026-86056)

Vulnerability from cvelistv5 – Published: 2026-09-22 17:14 – Updated: 2026-09-22 17:40
VLAI
Title
Notepad++: Null pointer dereference in NPPM_SAVESESSION message handler causes crash (DoS)
Summary
Notepad++ is a free and open-source source code editor. Prior to 8.9.8, the NPPM_SAVESESSION handler in PowerEditor/src/NppBigSwitch.cpp converts lParam to a sessionInfo pointer and dereferences its nbFile, files, and sessionFilePathName members without checking for null. A process running at the same or a higher Windows integrity level on the same desktop can send NPPM_SAVESESSION with a null lParam, immediately terminating Notepad++ and causing denial of service and loss of unsaved documents. This issue is fixed in version 8.9.8.
Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-22 17:40 UTC
CWE
  • CWE-476 - NULL Pointer Dereference
Assigner
References
Impacted products
Vendor Product Version CPE status
notepad-plus-plus notepad-plus-plus Affected: < 8.9.8
guessed Create a notification for this product.
Show details on NVD website
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