VDB-370263 · CVE-2026-11604 · WID-SEC-2026-1892

OpenVPN ovpn-dco-win up to 2.5.8 Epoch Key Generator buffer size

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2.5	$0-$5k	0.00

Summaryinfo

A vulnerability was found in OpenVPN ovpn-dco-win up to 2.5.8. It has been classified as problematic. This vulnerability affects unknown code of the component Epoch Key Generator. Performing a manipulation results in buffer size. This vulnerability was named CVE-2026-11604. The attack needs to be approached locally. There is no available exploit.

Detailsinfo

A vulnerability, which was classified as problematic, was found in OpenVPN ovpn-dco-win up to 2.5.8. This affects an unknown code block of the component Epoch Key Generator. The manipulation with an unknown input leads to a buffer size vulnerability. CWE is classifying the issue as CWE-131. The product does not correctly calculate the size to be used when allocating a buffer, which could lead to a buffer overflow. This is going to have an impact on availability. The summary by CVE is:

An incorrect buffer size calculation in the epoch key generator in OpenVPN ovpn-dco-win version 2.0.0 through 2.8.3 allows a remote authenticated peer to trigger a heap-based buffer overflow and kernel memory corruption via a crafted data packet, resulting in a system crash (denial of service).

It is possible to read the advisory at github.com. This vulnerability is uniquely identified as CVE-2026-11604 since 06/08/2026. The exploitability is told to be difficult. Attacking locally is a requirement. The technical details are unknown and an exploit is not publicly available.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2026-1892). Be aware that VulDB is the high quality source for vulnerability data.

Affected

Open Source OpenVPN

Productinfo

Type

Network Encryption Software

Vendor

OpenVPN

Name

ovpn-dco-win

Version

License

open-source

Website

Product: https://github.com/OpenVPN/ovpn-dco-win/

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 2.5
VulDB Meta Temp Score: 2.5

VulDB Base Score: 2.5
VulDB Temp Score: 2.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AV	AC	Au	C	I	A
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Buffer size
CWE: CWE-131 / CWE-120 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

06/08/2026 CVE reserved
06/11/2026 +3 days Advisory disclosed
06/11/2026 +0 days VulDB entry created
06/11/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-11604 (🔒)
GCVE (CVE): GCVE-0-2026-11604
GCVE (VulDB): GCVE-100-370263
CERT Bund: WID-SEC-2026-1892 - OpenVPN: Schwachstelle ermöglicht Denial of Service

Entryinfo

Created: 06/11/2026 07:38
Updated: 06/11/2026 16:55
Changes: 06/11/2026 07:38 (65), 06/11/2026 16:55 (7)
Complete: 🔍
Cache ID: 216::103