Cyber Resilience

CVE-2023-40036

Memory Safety in Notepad-Plus-Plus Notepad\+\+ ≤ 8.5.6

Public PoCMemory Safety
Published
25 August 2023
Modified
21 November 2024
CVSS Score v3.1 5.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
EPSS Score 0.0043 35th percentile
Risk Priority 35 floored blend · peak EPSS

Summary

CVE-2023-40036 is a medium-severity Classic Buffer Overflow (CWE-120) vulnerability in Notepad-Plus-Plus Notepad\+\+. Its CVSS base score is 5.5 (Medium).

Operationally, ranked at the 35th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability Data

Notepad++ is a free and open-source source code editor. Versions 8.5.6 and prior are vulnerable to global buffer read overflow in `CharDistributionAnalysis::HandleOneChar`. The exploitability of this issue is not clear. Potentially, it may be used to leak internal memory allocation…

more

information. As of time of publication, no known patches are available in existing versions of Notepad++.

CWE(s)

Related Threats

CVEs Like This One

CVE-2023-40164Same product: Notepad-Plus-Plus Notepad\+\+
CVE-2023-40166Same product: Notepad-Plus-Plus Notepad\+\+
CVE-2023-40031Same product: Notepad-Plus-Plus Notepad\+\+
CVE-2025-15556Same product: Notepad-Plus-Plus Notepad\+\+
CVE-2026-48770Same product: Notepad-Plus-Plus Notepad\+\+
CVE-2026-52884Same product: Notepad-Plus-Plus Notepad\+\+
CVE-2026-48800Same product: Notepad-Plus-Plus Notepad\+\+
CVE-2026-52885Same product: Notepad-Plus-Plus Notepad\+\+
CVE-2026-46710Same product: Notepad-Plus-Plus Notepad\+\+
CVE-2026-25926Same product: Notepad-Plus-Plus Notepad\+\+

Affected Assets

notepad-plus-plus
notepad\+\+
≤ 8.5.6

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V5.2.1

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-120

Platform-independent managed code eliminates the need for unchecked native buffer copies that are the root cause of classic buffer overflows.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure development practices directly enforce bounds checking and input validation that prevent classic buffer overflows.

ID.RA-01 partial match
prevents

Vulnerability identification processes such as code review or scanning detect classic buffer overflows before exploitation.

PR.PS-02 partial match
prevents

Routine patching replaces vulnerable code containing unchecked buffer copies with corrected versions.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

prevents

Secure coding directly requires bounds-checked memory operations, addressing the root cause of CWE-120.

detects

Security testing in development and acceptance can detect buffer overflows through fuzzing and static analysis, though it does not prevent them at the source.

prevents

Secure development life cycle mandates processes that can include input validation and bounds checking to prevent buffer overflows.

prevents

Application security requirements can specify input-size validation and safe buffer handling to mitigate classic buffer overflows.

prevents

Secure system architecture and engineering principles promote defensive coding patterns that reduce the likelihood of unchecked buffer copies.

References