CVE-2026-81738 PUBLISHED

Assigner: OpenVPN
Reserved: 27.08.2026 Published: 07.09.2026 Updated: 07.09.2026

OpenVPN 2.5.0 through 2.7.6 on Windows using the tap-windows6 driver allows attackers to trigger an out-of-bounds write via crafted DOMAIN-SEARCH entries

Metrics

CVSS 4.0

CVSS Vector: CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:P/VC:N/VI:L/VA:L/SC:N/SI:L/SA:L
CVSS Score: 2.3

Exploitability Metrics		Vulnerable System Impact Metrics		Subsequent System Impact Metrics
Attack Vector	Network	Confidentiality	None	Confidentiality	None
Attack Complexity	High	Integrity	Low	Integrity	Low
Attack Requirements	Present	Availability	Low	Availability	Low
Privileges Required	None
User Interaction	Passive

CVSS 4.0

Product Status

Vendor	OpenVPN
Product	OpenVPN
Versions	Default: unaffected affected from 2.5.0 to 2.7.6 (incl.)

References

https://community.openvpn.net/Security%20Announcements/CVE-2026-81738

Problem Types

CWE-121 Stack-based buffer overflow CWE
CWE-193 Off-by-one error CWE
CWE-787 Out-of-bounds write CWE