CVE-2026-860547.8HighCWE-121

CVE-2026-86054: Notepad++: Stack Buffer Overflow in `NppParameters::writeSession` via overlong session path

notepad-plus-plus

Affected: notepad-plus-plus · Exploitation: unlikely (under 1%)

Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.

0.2%probability of exploitation in the next 30 days

13th percentile

050100

Higher than 13% of scored CVEs

7.8HighCVSS 3.1

LowMediumHighCrit.

DescriptionCVE.org

Notepad++ is a free and open-source source code editor. Prior to 8.9.8, Notepad++ contains a stack buffer overflow in NppParameters::writeSession in PowerEditor/src/Parameters.cpp because it copies a session path derived from -settingsDir= into backupPathName[MAX_PATH] with unbounded wcscpy and appends SESSION_BACKUP_EXT with unbounded wcscat. A sufficiently long settings directory causes the backup suffix to exceed the fixed stack buffer when Notepad++ saves the session, and the protected release build terminates through its stack canary, causing denial of service. This issue is fixed in version 8.9.8.

Affected products1

From the CVE record. A product or version that is not listed is unknown, not unaffected.

notepad-plus-plus · notepad-plus-plus< 8.9.8

On the Atlas

Every published CVE is on the CyberSIXT Atlas, grouped by weakness, vendor and month.

Open the Atlas

Exploitation: Unlikely (under 1%). EPSS under 1%, or no score yet.
CISA KEV: Not listed
Public check: No public nuclei template
Weakness: Stack-based Buffer Overflow · Memory Corruption
Vendor: notepad-plus-plus
Published: September 2026
Band: Unlikely (under 1%), September 2026

CoverageNo articles yet

No CyberSIXT article names CVE-2026-86054 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.