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TI-2021-08886 Aliases CVE-2021-27393GHSA-x7x4-r59j-h6w9

A vulnerability has been identified in Nucleus NET (All versions), Nucleus ReadyStart V3…

Priority LOW 25CWE-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 · NVD. Fix status from CNA.

Summary

A vulnerability has been identified in Nucleus NET (All versions), Nucleus ReadyStart V3 (All versions < V2013.08), Nucleus Source Code (Versions including affected DNS modules). The DNS client does not properly randomize UDP port numbers of DNS requests. That could allow an attacker to poison the DNS cache or spoof DNS resolving.

Why it matters now

EPSS 0.00751 55th percentileScored 2026-11-07
Fix Fixed Nucleus ReadyStart V3 (Siemens): V2013.08

SSVC decision points

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

Affected products

VendorProductAffected versionsFixed inStatusSource
SiemensNucleus NETAll versions—No fix listedCNA
SiemensNucleus ReadyStart V3before V2013.08V2013.08Patch availableCNA
SiemensNucleus Source CodeVersions including affected DNS modules—No fix listedCNA
  • Nucleus NET VendorSiemens Affected All versions Fixed in — No fix listed CNA
  • Nucleus ReadyStart V3 VendorSiemens Affected before V2013.08 Fixed in V2013.08 Patch available CNA
  • Nucleus Source Code VendorSiemens Affected Versions including affected DNS modules Fixed in — No fix listed CNA

CPE configurations NVD · 3

CPEVersionsRoleVendor
cpe:2.3:a:siemens:nucleus_net:*:*:*:*:*:*:*:*all versionsVulnerableSiemens
cpe:2.3:a:siemens:nucleus_readystart_v3:*:*:*:*:*:*:*:*before 2013.08VulnerableSiemens
cpe:2.3:a:siemens:nucleus_source_code:-:*:*:*:*:*:*:*not specified by NVDVulnerableSiemens
  • cpe:2.3:a:siemens:nucleus_net:*:*:*:*:*:*:*:* Versions all versions Vulnerable ·Siemens
  • cpe:2.3:a:siemens:nucleus_readystart_v3:*:*:*:*:*:*:*:* Versions before 2013.08 Vulnerable ·Siemens
  • cpe:2.3:a:siemens:nucleus_source_code:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Siemens

Remediation

  • Fix · CNA Nucleus ReadyStart V3 (Siemens) Fixed in V2013.08

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-27393
  2. 2026-10-03 Alias added: GHSA-x7x4-r59j-h6w9

References

Advisory 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