PT-2025-39838 · Nanda Automation Technology · At Na2000

Zq-Star · Published 2025-09-29 · Updated 2025-12-23 · CVE-2025-56234

Positive Technologies (AI Summary)

CVSS v3.1

7.5

High

Base vector

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

Name of the Vulnerable Software and Affected Versions Nanda Automation Technology AT NA2000 (affected versions not specified)

Description The AT NA2000 Programmable Logic Controller (PLC) exhibits a denial-of-service condition. The device improperly handles TCP RST packets, accepting a broad range of sequence numbers instead of requiring an exact match to the expected sequence value, which is a deviation from RFC5961 standards. This allows attackers to disrupt established connections by sending numerous random TCP RST packets within the acceptable sequence number range, leading to a denial-of-service.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

DoS

Resource Exhaustion

Weakness Enumeration

CWE-400

Related Identifiers

CVE-2025-56234

Affected Products

At Na2000

References · 4

• https://nvd.nist.gov/vuln/detail/CVE-2025-56234 · Security Note
• https://twitter.com/CVEnew/status/2003567344363123060 · Twitter Post
• https://github.com/zq-star/TCP-Vuln-Report/blob/master/PLC/AT-NA2000/tcp-rst/at-na2000-tcp-rst.md · Note
• https://t.me/CVEtracker/33634 · Telegram Post