CVE-2026-52884

Summary

Notepad++ is a free and open-source source code editor. In v8.9.6.1, isInTrustedDirectory() does NOT canonicalize the path before checking. It uses a prefix-based check (PathIsPrefix() or equivalent) that matches paths starting with trusted directory strings. A path traversal using ....\ after a trusted directory prefix passes the check while resolving to an untrusted location. The CVE-2026-48800 patch adds isInTrustedDirectory() validation in Command::run() (RunDlg.cpp) before calling ShellExecute(). This function checks whether the resolved executable path is under a trusted directory. This vulnerability is fixed in 8.9.6.2.

Affected Software

VendorProductVersion RangeStatus
notepad-plus-plusnotepad-plus-plus= 8.9.6.1affected

Weaknesses

  • CWE-42: CWE-42: Path Equivalence: 'filename.' (Trailing Dot)

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: total

References