CVE-2026-12996: openvpn Out-of-bounds Read — Fix

Description

A use-after-free in OpenVPN 2.6.0 through 2.6.20 and 2.7_alpha1 through 2.7.4 allows remote authenticated peers to potentially cause a denial of service or leak memory via crafted packets during TLS session promotion or expiry

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CVSS v3.1 Score

8.1

HIGH

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H

EPSS — Exploit Prediction

0.0046

Probability of exploitation

0.38%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-125 Out-of-bounds Read

CWE-416 Use After Free

Affected Products

Vendor	Product	Versions
openvpn	openvpn	2.6.0 — 2.6.21
openvpn	openvpn	2.7 — 2.7.5
debian	debian_linux	All

References

Advisories & Patches

https://community.openvpn.net/Security%20Announcements/CVE-2026-12996

Other References

https://community.openvpn.net/ReleaseHistory#openvpn-2621-released-1-july-2026 https://community.openvpn.net/ReleaseHistory#openvpn-275-released-1-july-2026 https://lists.debian.org/debian-lts-announce/2026/07/msg00013.html

Frequently Asked Questions

What is CVE-2026-12996? +

A use-after-free in OpenVPN 2.6.0 through 2.6.20 and 2.7_alpha1 through 2.7.4 allows remote authenticated peers to potentially cause a denial of service or leak memory via crafted packets during TLS session promotion or expiry It has a CVSS v3.1 base score of 8.1 (HIGH).

How severe is CVE-2026-12996? +

CVE-2026-12996 has a CVSS v3.1 score of 8.1 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0046, placing it in the 0th percentile for exploitation probability.

What products are affected by CVE-2026-12996? +

CVE-2026-12996 affects products from debian, openvpn, specifically: debian_linux, openvpn. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2026-12996? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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