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TI-2021-07809 Aliases CVE-2021-25677GHSA-596h-hvjh-ffpf

A vulnerability has been identified in APOGEE PXC Compact (BACnet) (All versions <…

Priority LOW 26CWE-330Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · Low · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA.

Summary

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 V3 (All versions < V2017.02.4), 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), SIMOTICS CONNECT 400 (All versions >= V0.5.0.0 < V1.0.0.0), TALON TC Compact (BACnet) (All versions < V3.5.5), TALON TC Modular (BACnet) (All versions < V3.5.5). The DNS client does not properly randomize DNS transaction IDs. That could allow an attacker to poison the DNS cache or spoof DNS resolving.

Why it matters now

EPSS 0.01061 64th percentileScored 2026-11-07
Fix Fixed APOGEE PXC Compact (BACnet) (Siemens): V3.5.5APOGEE PXC Compact (P2 Ethernet) (Siemens): V2.8.20+7 more products

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
SiemensAPOGEE PXC Compact (BACnet)before V3.5.5V3.5.5Patch availableCNA
SiemensAPOGEE PXC Compact (P2 Ethernet)before V2.8.20V2.8.20Patch availableCNA
SiemensAPOGEE PXC Modular (BACnet)before V3.5.5V3.5.5Patch availableCNA
SiemensAPOGEE PXC Modular (P2 Ethernet)before V2.8.20V2.8.20Patch availableCNA
SiemensNucleus NETAll versions—No fix listedCNA
SiemensNucleus ReadyStart V3before V2017.02.3V2017.02.3Patch availableCNA
SiemensNucleus ReadyStart V3before V2017.02.4V2017.02.4Patch availableCNA
SiemensNucleus ReadyStart V4before V4.1.0V4.1.0Patch availableCNA
SiemensNucleus Source CodeVersions including affected DNS modules—No fix listedCNA
SiemensSIMOTICS CONNECT 400before V0.5.0.0V0.5.0.0Patch availableCNA
SiemensSIMOTICS CONNECT 400All versions >= V0.5.0.0 < V1.0.0.0—No fix listedCNA
SiemensTALON TC Compact (BACnet)before V3.5.5V3.5.5Patch availableCNA
SiemensTALON TC Modular (BACnet)before V3.5.5V3.5.5Patch availableCNA
  • APOGEE PXC Compact (BACnet) VendorSiemens Affected before V3.5.5 Fixed in V3.5.5 Patch available CNA
  • APOGEE PXC Compact (P2 Ethernet) VendorSiemens Affected before V2.8.20 Fixed in V2.8.20 Patch available CNA
  • APOGEE PXC Modular (BACnet) VendorSiemens Affected before V3.5.5 Fixed in V3.5.5 Patch available CNA
  • APOGEE PXC Modular (P2 Ethernet) VendorSiemens Affected before V2.8.20 Fixed in V2.8.20 Patch available CNA
  • Nucleus NET VendorSiemens Affected All versions Fixed in — No fix listed CNA
  • Nucleus ReadyStart V3 VendorSiemens Affected before V2017.02.3 Fixed in V2017.02.3 Patch available CNA
  • Nucleus ReadyStart V3 VendorSiemens Affected before V2017.02.4 Fixed in V2017.02.4 Patch available CNA
  • Nucleus ReadyStart V4 VendorSiemens Affected before V4.1.0 Fixed in V4.1.0 Patch available CNA
  • Nucleus Source Code VendorSiemens Affected Versions including affected DNS modules Fixed in — No fix listed CNA
  • SIMOTICS CONNECT 400 VendorSiemens Affected before V0.5.0.0 Fixed in V0.5.0.0 Patch available CNA
  • SIMOTICS CONNECT 400 VendorSiemens Affected All versions >= V0.5.0.0 < V1.0.0.0 Fixed in — No fix listed CNA
  • TALON TC Compact (BACnet) VendorSiemens Affected before V3.5.5 Fixed in V3.5.5 Patch available CNA
  • TALON TC Modular (BACnet) VendorSiemens Affected before V3.5.5 Fixed in V3.5.5 Patch available CNA

CPE configurations NVD · 6

CPEVersionsRoleVendor
cpe:2.3:o:siemens:simotics_connect_400_firmware:*:*:*:*:*:*:*:*0.5.0.0VulnerableSiemens
cpe:2.3:h:siemens:simotics_connect_400:-:*:*:*:*:*:*:*not specified by NVDRunning onSiemens
cpe:2.3:a:siemens:nucleus_net:*:*:*:*:*:*:*:*all versionsVulnerableSiemens
cpe:2.3:a:siemens:nucleus_readystart_v3:*:*:*:*:*:*:*:*before 2017.02.4VulnerableSiemens
cpe:2.3:a:siemens:nucleus_readystart_v4:*:*:*:*:*:*:*:*before 4.1.0VulnerableSiemens
cpe:2.3:a:siemens:nucleus_source_code:-:*:*:*:*:*:*:*not specified by NVDVulnerableSiemens
  • cpe:2.3:o:siemens:simotics_connect_400_firmware:*:*:*:*:*:*:*:* Versions 0.5.0.0 Vulnerable ·Siemens
  • cpe:2.3:h:siemens:simotics_connect_400:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Siemens
  • cpe:2.3:a:siemens:nucleus_net:*:*:*:*:*:*:*:* Versions all versions Vulnerable ·Siemens
  • cpe:2.3:a:siemens:nucleus_readystart_v3:*:*:*:*:*:*:*:* Versions before 2017.02.4 Vulnerable ·Siemens
  • cpe:2.3:a:siemens:nucleus_readystart_v4:*:*:*:*:*:*:*:* Versions before 4.1.0 Vulnerable ·Siemens
  • cpe:2.3:a:siemens:nucleus_source_code:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Siemens

Remediation

  • Fix · CNA APOGEE PXC Compact (BACnet) (Siemens) Fixed in V3.5.5
  • Fix · CNA APOGEE PXC Compact (P2 Ethernet) (Siemens) Fixed in V2.8.20
  • Fix · CNA APOGEE PXC Modular (BACnet) (Siemens) Fixed in V3.5.5
  • Fix · CNA APOGEE PXC Modular (P2 Ethernet) (Siemens) Fixed in V2.8.20
  • Fix · CNA Nucleus ReadyStart V3 (Siemens) Fixed in V2017.02.3
  • Fix · CNA Nucleus ReadyStart V3 (Siemens) Fixed in V2017.02.4
  • Fix · CNA Nucleus ReadyStart V4 (Siemens) Fixed in V4.1.0
  • Fix · CNA SIMOTICS CONNECT 400 (Siemens) Fixed in V0.5.0.0
  • Fix · CNA TALON TC Compact (BACnet) (Siemens) Fixed in V3.5.5
  • Fix · CNA TALON TC Modular (BACnet) (Siemens) Fixed in V3.5.5

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-25677
  2. 2026-10-03 Alias added: GHSA-596h-hvjh-ffpf

References

Patch 2

Other 1

  • TI-2021-11875 Out-of-bounds write in Siemens APOGEE MBC CVSS 3.1CRITICAL 9.8
  • TI-2022-17998 Uncontrolled resource consumption in Siemens APOGEE MBC CVSS 4.0HIGH 8.7
  • TI-2021-11873 A vulnerability has been identified in APOGEE MBC (PPC) (BACnet) (All versions), APOGEE… CVSS 3.1CRITICAL 9.8
  • TI-2020-16432 Out-of-bounds write in Siemens APOGEE PXC Compact CVSS 3.1HIGH 8.1
  • TI-2020-12430 Out-of-bounds write in Siemens APOGEE PXC Compact CVSS 3.1HIGH 8.1
  • TI-2021-11879 A vulnerability has been identified in Capital Embedded AR Classic 431-422 (All… CVSS 3.1CRITICAL 9.1
See all 24 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences