CVE-2017-7520
HighSummary
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.
Risk Assessment
An attacker could remotely disrupt the VPN service or gain access to sensitive information, posing a serious security threat to the organization.
Recommendation
It is recommended to upgrade OpenVPN to version 2.4.3 or 2.3.17 to mitigate the risks associated with this vulnerability.
Other vulnerabilities in OpenVPN
See all- CVE-2026-88964High
An integer underflow in OpenVPN version 2.7_alpha3 through 2.7.7 on Windows and Android allows remote authenticated servers to cause a denial of service or memory disclosure via crafted domain search options.
- CVE-2026-84790High
OpenVPN 2.7_alpha1 through 2.7.7 allows remote authenticated users to impersonate others via a crafted certificate subject field.
- 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-2026-84732High
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.
- CVE-2026-84256High
An argument parsing issue in OpenVPN 2.1_rc10 through 2.6.22 and 2.7_alpha1 through 2.7.7 on Windows allows remote authenticated users to execute arbitrary commands via a crafted certificate subject. The vulnerability affects the Windows platform.
Original NVD description (English source)
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.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS