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TI-2021-07796 Aliases CVE-2021-25664GHSA-q7wx-433j-27hv

Infinite loop in Siemens Capital Embedded AR Classic 431-422

Priority MEDIUM 41CWE-835Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-835.

Summary

A vulnerability has been identified in Capital Embedded AR Classic 431-422 (All versions), Capital Embedded AR Classic R20-11 (All versions < V2303), Nucleus NET (All versions), Nucleus ReadyStart V3 (All versions < V2017.02.4), Nucleus ReadyStart V4 (All versions < V4.1.0), Nucleus Source Code (All versions including affected IPv6 stack). The function that processes the Hop-by-Hop extension header in IPv6 packets and its options lacks any checks against the length field of the header, allowing attackers to put the function into an infinite loop by supplying arbitrary length values.

Why it matters now

EPSS 0.01885 79th percentileScored 2026-11-07
Fix Fixed Capital Embedded AR Classic R20-11 (Siemens): V2303Nucleus ReadyStart V3 (Siemens): V2017.02.4+1 more product

SSVC decision points

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

Affected products

VendorProductAffected versionsFixed inStatusSource
SiemensCapital Embedded AR Classic 431-422all versions—No fix listedCNA
SiemensCapital Embedded AR Classic R20-11before V2303V2303Patch availableCNA
SiemensNucleus NETAll versions—No fix listedCNA
SiemensNucleus ReadyStart V3before V2017.02.4V2017.02.4Patch availableCNA
SiemensNucleus ReadyStart V4before V4.1.0V4.1.0Patch availableCNA
SiemensNucleus Source Codeall versions—No fix listedCNA
  • Capital Embedded AR Classic 431-422 VendorSiemens Affected all versions Fixed in — No fix listed CNA
  • Capital Embedded AR Classic R20-11 VendorSiemens Affected before V2303 Fixed in V2303 Patch available CNA
  • Nucleus NET VendorSiemens Affected All versions Fixed in — No fix listed 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 all versions Fixed in — No fix listed CNA

CPE configurations NVD · 5

CPEVersionsRoleVendor
cpe:2.3:a:siemens:capital_vstar:-:*:*:*:*:*:*:*not specified by NVDVulnerableSiemens
cpe:2.3:a:siemens:nucleus_net:-:*:*:*:*:*:*:*not specified by NVDVulnerableSiemens
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:a:siemens:capital_vstar:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Siemens
  • cpe:2.3:a:siemens:nucleus_net:-:*:*:*:*:*:*:* Versions not specified by NVD 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 Capital Embedded AR Classic R20-11 (Siemens) Fixed in V2303
  • Fix · CNA Nucleus ReadyStart V3 (Siemens) Fixed in V2017.02.4
  • Fix · CNA Nucleus ReadyStart V4 (Siemens) Fixed in V4.1.0

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    Siemens Capital Embedded AR Classic R20-11, Nucleus ReadyStart V3, Nucleus ReadyStart V4 V2017.02.4, V2303, V4.1.0

    2 records Highest priority Priority MEDIUM 2 MEDIUM

    Other records, highest priority first

    • TI-2021-07795 Infinite loop in Siemens Capital Embedded AR Classic 431-422Priority MEDIUM 41
    Show all 2 records →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-25664
  2. 2026-10-03 Alias added: GHSA-q7wx-433j-27hv

References

Advisory 2

Other 1

  • TI-2021-11873 A vulnerability has been identified in APOGEE MBC (PPC) (BACnet) (All versions), APOGEE… CVSS 3.1CRITICAL 9.8
  • TI-2021-11879 A vulnerability has been identified in Capital Embedded AR Classic 431-422 (All… CVSS 3.1CRITICAL 9.1
  • TI-2021-11878 Integer underflow in Siemens Capital Embedded AR Classic 431-422 CVSS 3.1CRITICAL 9.1
  • TI-2021-11490 A vulnerability has been identified in Capital Embedded AR Classic 431-422 (All… CVSS 3.1CRITICAL 9.1
  • TI-2021-11489 A vulnerability has been identified in Capital Embedded AR Classic 431-422 (All… CVSS 3.1CRITICAL 9.1
  • TI-2021-07795 Infinite loop in Siemens Capital Embedded AR Classic 431-422 CVSS 4.0HIGH 8.7
See all 13 →

Sources

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