CVE-2026-5525
Stack-Based Buffer Overflow in Notepad++ File Drop Handler leads to DoS
A stack-based buffer overflow vulnerability exists in Notepad++ version 8.9.3 in the file drop handler component. 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, resulting in a stack buffer overflow and application crash (STATUS_STACK_BUFFER_OVERRUN).
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- High
- Privileges needed
- Low
- User interaction
- Required
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Stack-Based Buffer Overflow in Notepad++ File Drop Handler leads to DoS
A stack-based buffer overflow vulnerability exists in Notepad++ version 8.9.3 in the file drop handler component. 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, resulting in a stack buffer overflow and application crash (STATUS_STACK_BUFFER_OVERRUN).
- Record
CVE-2026-5525- CVSS 3.1
- 6.0 Medium
CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:N - Weakness
- CWE-121
- Updated
- 2026-11-02
EUVDEUVD-2026-21334
A stack-based buffer overflow vulnerability exists in Notepad++ version 8.9.3 in the file drop handler component. 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, resulting in a stack buffer overflow and application crash (STATUS_STACK_BUFFER_OVERRUN).
- Record
EUVD-2026-21334- CVSS 3.1
- 6.0 Medium
CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-8hrp-2fqv-gvrx
A stack-based buffer overflow vulnerability exists in Notepad++ version 8.9.3 in the file drop...
A stack-based buffer overflow vulnerability exists in Notepad++ version 8.9.3 in the file drop handler component. 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, resulting in a stack buffer overflow and application crash (STATUS_STACK_BUFFER_OVERRUN).
- Record
GHSA-8hrp-2fqv-gvrx- CVSS 3.1
- 6.0 Medium
CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:N - Weakness
- CWE-121
- Updated
- 2026-11-02
NVD
A stack-based buffer overflow vulnerability exists in Notepad++ version 8.9.3 in the file drop handler component. 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, resulting in a stack buffer overflow and application crash (STATUS_STACK_BUFFER_OVERRUN).
- Record
CVE-2026-5525- CVSS 3.1
- 6.0 Medium
CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:N - CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-121
- Updated
- 2026-11-02
OSV
A stack-based buffer overflow vulnerability exists in Notepad++ version 8.9.3 in the file drop handler component. 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, resulting in a stack buffer overflow and application crash (STATUS_STACK_BUFFER_OVERRUN).
- Record
CVE-2026-5525- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-5525 is a medium vulnerability (CVSS 6.0) in Notepad++, published April 10, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.17%, the 6th percentile. No source names a fixed version.