CVE-2020-27738

HIGH
7.4
CVSS Score
Published: April 22, 2021 at 08:42 PM UTC
Updated: June 17, 2026 at 03:09 AM UTC
12 products affected across 1 vendorNucleus NETNucleus ReadyStart V3Nucleus ReadyStart V4

Using APOGEE PXC Compact (BACnet) by Siemens?

Get instant alerts when new vulnerabilities affect APOGEE PXC Compact (BACnet) - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Severity
HIGH7.4
Exploit prediction
EPSS 4%

Description

A vulnerability has been identified in APOGEE PXC Compact (BACnet) (All versions < V3.5.5), APOGEE PXC Compact (P2 Ethernet) (All versions < V2.8.20), APOGEE PXC Modular (BACnet) (All versions < V3.5.5), APOGEE PXC Modular (P2 Ethernet) (All versions < V2.8.20), Nucleus NET (All versions), Nucleus ReadyStart V3 (All versions < V2017.02.3), Nucleus ReadyStart V4 (All versions < V4.1.0), Nucleus Source Code (Versions including affected DNS modules), SIMOTICS CONNECT 400 (All versions < V0.5.0.0), TALON TC Compact (BACnet) (All versions < V3.5.5), TALON TC Modular (BACnet) (All versions < V3.5.5). The DNS domain name record decompression functionality does not properly validate the pointer offset values. The parsing of malformed responses could result in a read access past the end of an allocated structure. An attacker with a privileged position in the network could leverage this vulnerability to cause a denial-of-service condition.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

All versions
Affected range stops below 2017.02.3, so it looks safe — our inference, not a vendor statement
Affected range stops below 4.1.0, so it looks safe — our inference, not a vendor statement
Affected range stops below 0.5.0.0, so it looks safe — our inference, not a vendor statement
siemens-simotics-connect-400 (same device)

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

CVSS

Attack Vector
NETWORK
Complexity
HIGH
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-788CWE-119

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Free plan, no card