CVE-2026-78221 PUBLISHED

Assigner: OpenVPN
Reserved: 26.08.2026 Published: 07.09.2026 Updated: 07.09.2026

An incorrect buffer size calculation in the Windows Interactive Service in OpenVPN 2.7_alpha1 through 2.7.6 allows local authenticated users to cause memory corruption or disclose sensitive information via crafted NRPT inputs.

Metrics

CVSS 4.0

CVSS Vector: CVSS:4.0/AV:L/AC:H/AT:P/PR:L/UI:P/VC:H/VI:N/VA:H/SC:H/SI:N/SA:H
CVSS Score: 5.9

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

CVSS 4.0

Product Status

Vendor	OpenVPN
Product	OpenVPN
Versions	Default: unaffected affected from 2.7_alpha1 to 2.7.6 (incl.)

References

https://community.openvpn.net/Security%20Announcements/CVE-2026-78221

Problem Types

CWE-131 Incorrect calculation of buffer size CWE