CVE-2026-84732
HighCVSS 8.7Exploitation Probability (EPSS)
Low risk44th percentile - higher than 44% of all known CVEs
Summary
In OpenVPN through 2.6.22 and 2.7.6, retransmissions of ACK packet ID allow remote unauthenticated attackers to cause a denial of service via crafted inputs that trigger a timeout integer overflow.
Risk Assessment
Risk of VPN service disruption, potentially leading to network unavailability for users.
Recommendation
Update OpenVPN to a patched version or apply available mitigations to reduce risk.
Other vulnerabilities in OpenVPN
See all- CVE-2017-7520High
OpenVPN versions before 2.4.3 and before 2.3.17 are vulnerable to denial-of-service and/or possibly sensitive memory leak triggered by man-in-the-middle attacker.
- CVE-2017-7508High
OpenVPN versions before 2.4.3 and before 2.3.17 are vulnerable to remote denial-of-service when receiving malformed IPv6 packet.
- CVE-2017-7478High
OpenVPN version 2.3.12 and newer is vulnerable to unauthenticated Denial of Service of server via received large control packet. This issue is fixed in 2.3.15 and 2.4.2.
- CVE-2026-13379Critical
The Windows interactive service in OpenVPN (versions 2.7_alpha1 through 2.7.4) allows remote attackers to cause persistent DNS state pollution or a service crash via a crafted search domain during disconnection.
- CVE-2025-12106Critical
Insufficient argument validation in OpenVPN 2.7_alpha1 through 2.7_rc1 allows an attacker to trigger a heap buffer over-read when parsing IP addresses.
- CVE-2023-46850Critical
OpenVPN versions 2.6.0 to 2.6.6 contain a use after free vulnerability that may lead to undefined behavior, leaking memory buffers, or remote code execution when sending network buffers to a remote peer.
- CVE-2017-12166Critical
OpenVPN versions before 2.3.3 and 2.4.x before 2.4.4 are vulnerable to a buffer overflow vulnerability when key-method 1 is used, possibly resulting in code execution.
- CVE-2026-84256High
An argument parsing issue in OpenVPN 2.1_rc10 through 2.6.22 and 2.7_alpha1 through 2.7.6 on Windows allows remote authenticated users to execute arbitrary commands via a crafted certificate subject.
- CVE-2026-84226High
OpenVPN version 2.5.0 through 2.6.22 and 2.7_alpha1 through 2.7.6 on Windows allows local authenticated users to perform a binary planting attack during network configuration steps.
- CVE-2026-82312Low
OpenVPN versions 2.0.0 through 2.6.22 and 2.7_alpha1 through 2.7.6 on Windows allows local authenticated users to cause a denial of service via a NULL DACL on named IPC objects.
Original NVD description (English source)
Retransmissions of ACK packet ID in OpenVPN through 2.6.22 and 2.7.6 allow remote unauthenticated attackers to cause a denial of service via crafted inputs that trigger a timeout integer overflow

