CVE-2026-45265

What it is

BACnet Stack is a BACnet open source protocol stack C library for embedded systems. Prior to versions 1.4.4 and 1.5.1, there is a stack-based out-of-bounds write / stack-buffer-overflow in bacnet-stack when the server processes a malicious Atomic-Read-File request in record access mode. The bug is triggered on the real server side. A crafted request can set an excessively large RecordCount, which is later used as the loop bound for writing record data into a stack-allocated BACNET_ATOMIC_READ_FILE_DATA data structure. However, the stack object only has space for one fileData element. When the loop reaches i = 1, the code computes &data->fileData[1], which is already out of bounds, and the resulting invalid pointer is passed down to memmove(), causing a stack-buffer-overflow. This issue has been patched in versions 1.4.4 and 1.5.1.

At a glance

Exploitability

Can be exploited over the network without logging in. High risk of service disruption.

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2026-05-11 18:41 UTC ReservedThe CVE id was reserved by its CNA
2. 2026-11-12 20:18 UTC PublishedDisclosed publicly on CVE.org and NVD
3. 2026-11-12 22:09 UTC Last updatedMost recent change to the record

Why it ranks here

• Exploited in the wild: no, CISA does not list it.
• Exploit odds: not scored yet.
• Severity: 8.2 HIGH (CVSS).
• Fix: a patch or advisory is linked.

Details

Published

2026-11-12 20:18 UTC

Last modified

2026-11-12 22:09 UTC

Weakness

CWE-121

Record status

Awaiting Analysis

Attack profile CVSS 3.1 · 8.2

Attack vector

Network

Complexity

Low

Privileges needed

None

User interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

Low

Availability

High

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2026-45265.md and follow it. Check whether this project is affected by CVE-2026-45265. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

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