Heap BOverflow via epoch key in OpenVPN ovpn-dco-win <=2.8.3
CVE-2026-11604 Published on June 10, 2026
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).
Weakness Types
Incorrect Calculation of Buffer Size
The software does not correctly calculate the size to be used when allocating a buffer, which could lead to a buffer overflow.
Heap-based Buffer Overflow
A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().
What is a Memory Corruption Vulnerability?
The software writes data past the end, or before the beginning, of the intended buffer. Typically, this can result in corruption of data, a crash, or code execution. The software may modify an index or perform pointer arithmetic that references a memory location that is outside of the boundaries of the buffer. A subsequent write operation then produces undefined or unexpected results.
CVE-2026-11604 has been classified to as a Memory Corruption vulnerability or weakness.
Affected Versions
OpenVPN ovpn-dco-win:- Version 2.0.0, <= 2.5.8 is affected.
Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.