CVE-2026-52886 PUBLISHED

Notepad++: session.xml backupFilePath starts_with Bypass

Assigner: GitHub_M
Reserved: 08.06.2026 Published: 17.08.2026 Updated: 17.08.2026

Notepad++ is a free and open-source source code editor. Prior to 8.9.7, Notepad++ validates the backupFilePath attribute from session.xml with std::wstring::starts_with against the expected backup directory without path normalization, allowing parent-directory sequences during snapshot-mode restoration to read an arbitrary user-readable file outside the backup directory into an editor tab. This issue is fixed in version 8.9.7.

Metrics

CVSS Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:P/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
CVSS Score: 5.1

Product Status

Vendor notepad-plus-plus
Product notepad-plus-plus
Versions
  • Version < 8.9.7 is affected

References

Problem Types

  • CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') CWE