7.1
HIGH CVSS 3.1
CVE-2026-52786
BACnet Stack: malicious ReadPropertyMultiple-ACK with excessive properties causes global-buffer-overflow in ProcessRPMData()
Description

BACnet Stack is a BACnet open source protocol stack C library for embedded systems. Prior to versions 1.4.5, 1.5.1, and 1.6.0, in the official apps/epics client tool on v1.6.0-rc1 (not in the generic BACnet RPM ACK decoder alone) a malicious BACnet/IP endpoint can reply to the EPICS tool’s legitimate ReadPropertyMultiple request with a syntactically valid ReadPropertyMultiple-ACK that contains more heading properties than the tool’s fixed local storage can hold. The response is decoded successfully and later consumed by ProcessRPMData(), which writes property values into a fixed global array using an unbounded linear index. This results in a reproducible global-buffer-overflow in apps/epics/main.c. This is a network-reachable memory corruption in the official epics tool’s response-processing path. The root cause is that apps/epics treats a remotely supplied variable-length RPM property list as if it were a trusted, fixed-size local heading-property set. This issue has been patched in versions 1.4.5, 1.5.1, and 1.6.0.

INFO

Published Date :

Nov. 12, 2026, 8:18 p.m.

Last Modified :

Nov. 12, 2026, 8:18 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-52786 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Bacnetstack bacnet_stack
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH [email protected]
Solution
Update BACnet Stack to patched versions to fix buffer overflow vulnerability.
  • Update BACnet Stack to version 1.4.5 or later.
  • Update BACnet Stack to version 1.5.1 or later.
  • Update BACnet Stack to version 1.6.0 or later.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-52786.

URL Resource
https://github.com/bacnet-stack/bacnet-stack/pull/1366
https://github.com/bacnet-stack/bacnet-stack/pull/1409
https://github.com/bacnet-stack/bacnet-stack/security/advisories/GHSA-c4q6-7827-mfg6
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-52786 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-52786 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-52786 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-52786 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Nov. 12, 2026

    Action Type Old Value New Value
    Added Description BACnet Stack is a BACnet open source protocol stack C library for embedded systems. Prior to versions 1.4.5, 1.5.1, and 1.6.0, in the official apps/epics client tool on v1.6.0-rc1 (not in the generic BACnet RPM ACK decoder alone) a malicious BACnet/IP endpoint can reply to the EPICS tool’s legitimate ReadPropertyMultiple request with a syntactically valid ReadPropertyMultiple-ACK that contains more heading properties than the tool’s fixed local storage can hold. The response is decoded successfully and later consumed by ProcessRPMData(), which writes property values into a fixed global array using an unbounded linear index. This results in a reproducible global-buffer-overflow in apps/epics/main.c. This is a network-reachable memory corruption in the official epics tool’s response-processing path. The root cause is that apps/epics treats a remotely supplied variable-length RPM property list as if it were a trusted, fixed-size local heading-property set. This issue has been patched in versions 1.4.5, 1.5.1, and 1.6.0.
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H
    Added CWE CWE-787
    Added CWE CWE-129
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/52xxx/CVE-2026-52786.json">CVE-2026-52786</a>
    Added Reference https://github.com/bacnet-stack/bacnet-stack/pull/1366
    Added Reference https://github.com/bacnet-stack/bacnet-stack/pull/1409
    Added Reference https://github.com/bacnet-stack/bacnet-stack/security/advisories/GHSA-c4q6-7827-mfg6
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.