CVE-2026-48778
HIGHNotepad++ is a free and open-source source code editor. Prior to 8.9.6.1, the <GUIConfig name="commandLineInterpreter"> tag in config.xml is read by NppXml::value() (Parameters.cpp:6430)…
Description
Notepad++ is a free and open-source source code editor. Prior to 8.9.6.1, the <GUIConfig name="commandLineInterpreter"> tag in config.xml is read by NppXml::value() (Parameters.cpp:6430) and stored in _nppGUI._commandLineInterpreter without any validation, whitelist, or digital signature check. When the user triggers IDM_FILE_OPEN_CMD (File → Open Containing Folder → cmd), NppCommands.cpp:228 creates a Command object with this value and calls run(), which invokes ShellExecute (RunDlg.cpp:221) with the attacker-controlled string as the executable path. This vulnerability is fixed in 8.9.6.1.
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Notepad++ 8.9.6 - Arbitrary Code Execution
by Kavin Jindal · May 30, 2026
Detection & mitigation playbook
VulnerabilityDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for the affected component. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Remediation status
No patched version of the affected component has shipped for CVE-2026-48778 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Mitigate without a patch
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-48778 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-48778. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-48778 in your dependencies?
O3 detects CVE-2026-48778 across dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.