Out-of-bounds Read in Openvpn
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 triggered during TLS session promotion.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.4 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:H.
EPSS exploit prediction
EPSS: 0.004 (30.0th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 30th percentile — 30.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.006 · newest: 0.004 · change: -0.002
Affected products
- Openvpn — versions 2.6.0, 2.7_alpha1
Weakness classification (CWE)
References
- community.openvpn.net/ReleaseHistory (release-notes, Release Notes)
- community.openvpn.net/ReleaseHistory (release-notes, Release Notes)
- community.openvpn.net/Security Announcements/CVE-2026-40215 (vendor-advisory, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-40215?
- CVE-2026-40215 is a high-severity vulnerability in Openvpn, classified under Out-of-bounds Read. CVSS score: 7.4/10. Published 2026-06-08.
- How severe is CVE-2026-40215?
- High severity. CVSS v3 base score is 7.4 out of 10.