PT-2025-20864 · Unknown · Bacnet Atec 550-441+3

Published 2025-05-13 · Updated 2025-05-13 · CVE-2025-40556

Positive Technologies (AI Summary)

CVSS v3.1

6.5

Medium

Base vector

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

Name of the Vulnerable Software and Affected Versions: BACnet ATEC 550-440 (All versions) BACnet ATEC 550-441 (All versions) BACnet ATEC 550-445 (All versions) BACnet ATEC 550-446 (All versions)

Description: A vulnerability has been identified in the affected devices, which improperly handle specific incoming BACnet MSTP messages. This could allow an attacker residing in the same BACnet network to send a specially crafted MSTP message, resulting in a denial of service condition of the targeted device. A power cycle is required to restore the device's normal operation.

Recommendations: For BACnet ATEC 550-440, consider restricting access to the BACnet network to minimize the risk of exploitation. For BACnet ATEC 550-441, consider implementing network segmentation to limit the attack surface. For BACnet ATEC 550-445, consider disabling unnecessary features that may be using the vulnerable MSTP message handling. For BACnet ATEC 550-446, consider implementing a firewall rule to block incoming BACnet MSTP messages from untrusted sources. At the moment, there is no information about a newer version that contains a fix for this vulnerability.

DoS

RCE

Weakness Enumeration

CWE-20

Related Identifiers

CVE-2025-40556

Affected Products

Bacnet Atec 550-440

Bacnet Atec 550-441

Bacnet Atec 550-445

Bacnet Atec 550-446

References · 4

• https://nvd.nist.gov/vuln/detail/CVE-2025-40556 · Security Note
• https://t.me/cvetracker/23715 · Telegram Post
• https://twitter.com/CVEnew/status/1922228931182178355 · Twitter Post
• https://cert-portal.siemens.com/productcert/html/ssa-828116.html · Note