What is the CVSS score of CVE-2023-40250?

CVE-2023-40250 has a CVSS 3.1 base score of 8.8 (High). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H. EPSS exploitation probability: 0.1%.

How to fix or mitigate CVE-2023-40250?

Within 30 days: Identify all affected systems and apply vendor patches as part of regular patch cycle. If patching is delayed, consider network segmentation to limit exposure.

Hcell CVE-2023-40250

HIGH

Classic Buffer Overflow (CWE-120)

2024-01-12 vuln@krcert.or.kr

Windows Buffer Overflow Microsoft Hcell Hancom

8.8

CVSS 3.1 · NVD

View

Vulnerability Assessment

Weakness	CWE CWE-120 OWASP Top 10:2025 A06:2021 - Vulnerable and Outdated Components ASVS 5.0 V15 - Secure Coding and Architecture Buffer copy size validation MITRE ATT&CK 1 technique across 1 tactic: Execution The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. Sign in to read
Impact	CVSS score of 8.8 (HIGH). Attack characteristics: network attack vector, low complexity, no privileges required, user interaction required. EPSS exploitation probability: 0.06%.
Exploit ScenarioDerived	A remote attacker could overflow a buffer to corrupt adjacent memory by sending crafted requests to the affected application. No authentication is required to exploit this vulnerability.

This Week Schedule remediation this week. Why: HIGH severity (CVSS 7.0-8.9).

No patch listed yet 0.1% exploitation probability (EPSS)

Get an e-mail when this CVE is exploited, patched or re-scored. Free account.

Alert me

AnalysisAIv1 – Mar 28, 2026

Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') vulnerability in Hancom HCell on Windows allows Overflow Buffers.0.0.893. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.

Earlier versions of this analysis (1)

v1 Mar 28, 2026 - 19:34 CVSS 8.8

Overflow in Hancom HCell.

RemediationAI

No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Always validate buffer sizes before copy operations. Use bounded functions (strncpy, snprintf). Enable compiler protections.

Affects your stack

Find out whether the stacks and servers you run are on an affected version.

Checking this CVE against your own stacks and servers is part of the Basic plan and up.

Technical ContextAI · show details

This vulnerability is classified as Buffer Copy without Size Check (CWE-120), which allows attackers to overflow a buffer to corrupt adjacent memory. Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') vulnerability in Hancom HCell on Windows allows Overflow Buffers.0.0.893. Affected products include: Hancom Hcell.

Severity by source

NVD PRIMARY 8.8 HIGH

AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

DescriptionCVE.org

Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') vulnerability in Hancom HCell on Windows allows Overflow Buffers.This issue affects HCell: 12.0.0.893.

Executive ViewAI

Why It Matters

CVE-2023-40250 presents significant security risk, a buffer overflow vulnerability rated CVSS 8.8. Exploitation could allow attackers to corrupt memory, crash the application, or potentially execute arbitrary code. Organizations should apply vendor updates when available and consider compensating controls in the interim.

Business Impact: Severe

Compensating Controls

Apply vendor patch. If immediate patching is not feasible: (1) Enable ASLR and DEP where available; (2) Implement network segmentation; (3) Monitor for exploitation indicators.

Threat Intelligence Overview

EPSS Score

0.1%

Top 81% exploitable

Data Quality

3 sources

Confidence: Low

NVD

CVE.org

EPSS

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue

Severity HIGH

CISA KEV No

Public POC No

EPSS 0.1%

Patch available No

Active threat No

Deciding rule

HIGH severity (CVSS 7.0-8.9)

What every action level means

Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.

Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.

This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.

This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.

Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

SSVC AssessmentENISA

SSVC Decision· derived

Scheduled

Exploitation· derived

None

System Exposure· derived

Open

Automatable· derived

Human Impact

Very High

Priority Score

Low Medium High Critical

KEV: 0

EPSS: 0

CVSS: +44

PoC: 0

Weaponized: 0

Threat intel: 0

Gov advisory: 0

Attack Technique

Buffer Overflow HIGH

A buffer overflow occurs when a program writes more data to a memory buffer than it was allocated to hold, causing the excess data to spill into adjacent memory regions.