Notepad++ is a free and open-source source code editor. Prior to 8.9.7, the expandNppEnvironmentStrs function in PowerEditor/src/WinControls/StaticDialog/RunDlg/RunDlg.cpp copies a Notepad++ variable name between $( and ) into the fixed-size wchar_t str[MAX_PATH] stack buffer without bounding the m loop index, allowing a name of 260 or more characters to corrupt adjacent stack data, terminate the process through __report_gsfailure, and potentially execute code. This issue is fixed in version 8.9.7.
{
"cna_assigner": "GitHub_M",
"cwe_ids": [
"CWE-121",
"CWE-787"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/54xxx/CVE-2026-54758.json"
}{
"extracted_events": [
{
"introduced": "0"
},
{
"fixed": "8.9.7"
}
],
"source": [
"AFFECTED_FIELD",
"REFERENCES"
]
}
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-54758.json"
[
{
"deprecated": false,
"digest": {
"line_hashes": [
"334229428646160504944987239565152517410",
"328969565235246161758957266620694167180",
"79929896174919516706123434099940561774",
"114755489084487219927720695514385785481",
"142349942459912568198982065847682283505",
"217168309658704598160461306797708685299",
"324123565846550223427109563758010586671"
],
"threshold": 0.9
},
"id": "CVE-2026-54758-6defd4c9",
"signature_type": "Line",
"signature_version": "v1",
"source": "https://github.com/notepad-plus-plus/notepad-plus-plus/commit/0a9527e9f7140a2323e25d14e362b46ee0efc3db",
"target": {
"file": "PowerEditor/src/WinControls/StaticDialog/RunDlg/RunDlg.cpp"
}
},
{
"deprecated": false,
"digest": {
"function_hash": "321789678466323583525587903832696399039",
"length": 2313
},
"id": "CVE-2026-54758-77046d11",
"signature_type": "Function",
"signature_version": "v1",
"source": "https://github.com/notepad-plus-plus/notepad-plus-plus/commit/6634650414ff91220a4c353b7fe5ad741af0f9f9",
"target": {
"file": "PowerEditor/src/WinControls/AboutDlg/AboutDlg.cpp",
"function": "AboutDlg::run_dlgProc"
}
},
{
"deprecated": false,
"digest": {
"function_hash": "266463837319559657867228992681787602376",
"length": 1561
},
"id": "CVE-2026-54758-bb4bda39",
"signature_type": "Function",
"signature_version": "v1",
"source": "https://github.com/notepad-plus-plus/notepad-plus-plus/commit/0a9527e9f7140a2323e25d14e362b46ee0efc3db",
"target": {
"file": "PowerEditor/src/WinControls/StaticDialog/RunDlg/RunDlg.cpp",
"function": "expandNppEnvironmentStrs"
}
},
{
"deprecated": false,
"digest": {
"line_hashes": [
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],
"threshold": 0.9
},
"id": "CVE-2026-54758-de8dc4ca",
"signature_type": "Line",
"signature_version": "v1",
"source": "https://github.com/notepad-plus-plus/notepad-plus-plus/commit/6634650414ff91220a4c353b7fe5ad741af0f9f9",
"target": {
"file": "PowerEditor/src/WinControls/AboutDlg/AboutDlg.cpp"
}
}
]
"2026-09-11T08:19:21Z"