CVE-2026-5525: Notepad++ · Stack-based Buffer Overflow
Affects Notepad++Source CVE Database V5
Not known to be exploited · CVSS 6.0 Medium.
Data as of 30 Oct 2026, 06:59 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 5% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:NExploitation evidence
Disclosed: evidence found.
CVE published 10 Apr 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Notepad++ ProjectNotepad++ | Affected
| Fixed in– |
GitHubnotepad-plus-plus/notepad-plus-pluspkg:github/notepad-plus-plus/notepad-plus-plusOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Until an official fix is released, users should avoid dragging and dropping directory paths of exactly 259 characters without trailing backslash into Notepad++ 8.9.3. Monitor vendor channels for updates and apply patches promptly once available.
Description
CVE-2026-5525 is a stack-based buffer overflow vulnerability in Notepad++ version 8.9.3. It occurs in the file drop handler when a user drags and drops a directory path of exactly 259 characters without a trailing backslash. The application appends a backslash and null terminator without proper bounds checking, causing a stack buffer overflow and application crash. The vulnerability has a medium severity with a CVSS score of 6. No patch or official remediation is currently available, and there are no known exploits in the wild.