Cyber Resilience

CVE-2024-1305

Memory Safety in Openvpn Tap-Windows6 ≤ 9.26.0

Published
08 July 2024
Modified
22 August 2025
Patch / advisory
CVSS Score v3.1 9.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.15 96th percentile
Risk Priority 82 floored blend · peak EPSS

Summary

CVE-2024-1305 is a critical-severity Integer Overflow or Wraparound (CWE-190) vulnerability in Openvpn Tap-Windows6. Its CVSS base score is 9.8 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked in the top 4% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SA-8 (Security and Privacy Engineering Principles) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

The vulnerability affects the tap-windows6 driver in versions 9.26 and earlier. It stems from insufficient validation of size data in incoming write operations, which permits memory buffer overflows. This is tracked as CWE-190 and carries a CVSS 3.1 score of 9.8, enabling outcomes that range from system bug checks to arbitrary code execution in kernel space.

Remote attackers can exploit the flaw over the network without authentication or user interaction. Successful exploitation grants full read, write, and control capabilities on the target system, affecting confidentiality, integrity, and availability.

Reference materials hosted by the OpenVPN community at the listed wiki and mailing-list URLs describe the issue and point to associated patches or updates for the affected driver. The EPSS score has remained flat at a peak of 0.0833 with no material increase observed after disclosure.

EU & UK References

Vulnerability Data

tap-windows6 driver version 9.26 and earlier does not properly check the size data of incomming write operations which an attacker can use to overflow memory buffers, resulting in a bug check and potentially arbitrary code execution in kernel space

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2024-5594Same vendor: Openvpn
CVE-2026-13117Same vendor: Openvpn
CVE-2026-40215Same vendor: Openvpn
CVE-2025-50054Same vendor: Openvpn
CVE-2026-11604Same vendor: Openvpn
CVE-2024-27459Same vendor: Openvpn
CVE-2024-49994Shared CWE-190
CVE-2026-37540Shared CWE-190
CVE-2026-24210Shared CWE-190
CVE-2026-53482Shared CWE-190

Affected Assets

openvpn
tap-windows6
≤ 9.26.0

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)
  • V5.2.6

Mitigating Controls (NIST 800-53 r5) AI

Developer testing and evaluation (static analysis, fuzzing, unit tests) directly finds integer overflow defects before deployment.

Secure engineering principles require use of safe arithmetic constructs or language features that structurally eliminate integer overflow during calculation.

Input validation enforces bounds on values before arithmetic, stopping the conditions that trigger overflow or wraparound.

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 SDLC practices directly require use of safe arithmetic, bounds checks, and testing that prevent integer overflows.

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.

finds

Security testing in development can detect integer overflows before release.

prevents

Secure SDLC mandates input validation and arithmetic checks that prevent integer overflows.

degrades

Application security requirements include bounds checking and safe arithmetic to avoid overflow conditions.

degrades

Secure architecture principles require defensive coding patterns that mitigate integer wraparound risks.

prevents

Secure coding standards explicitly forbid unsafe integer operations and mandate overflow-safe constructs.

References