High severity · published Jun 8, 2026
CVE-2026-40215
A race condition in OpenVPN 2.6.0 through 2.6.19 and 2.7_alpha1 through 2.7.1 allows remote attackers to potentially cause a server crash or leak heap memory via a use-after-free…
7.4
CVSS
0.4%
EPSS
No
On KEV
Description
A race condition in OpenVPN 2.6.0 through 2.6.19 and 2.7_alpha1 through 2.7.1 allows remote attackers to potentially cause a server crash or leak heap memory via a use-after-free triggered during TLS session promotion.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:H
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
High
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 31% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
OP
OpenVPN · OpenVPN
2.6.0 through 2.6.19; 2.7_alpha1 through 2.7.1 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-40215
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-40215
Release Notes
https://community.openvpn.net/ReleaseHistory#openvpn-2620-released-22-april-2026
Release Notes
https://community.openvpn.net/ReleaseHistory#openvpn-272-released-22-april-2026
Vendor Advisory
https://community.openvpn.net/Security%20Announcements/CVE-2026-40215
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