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CVE-2021-25664

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 ...

Published: Apr 22, 2021Updated: Mar 11, 2025 Sources: CVE List NVD csafCWE-835
7.5HIGH
NVD MITRE
EPSS Score
1.9%
Top 21.9%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
Not available

Description

The IPv6 stack of the networking component (Nucleus NET) in Nucleus Real-Time Operating System (RTOS) contains two vulnerabilities when processing IPv6 headers which could allow an attacker to cause a denial of service condition. Siemens has released new versions for several affected products and recommends to update to the latest versions. Siemens is preparing further fix versions and recommends countermeasures for products where fixes are not, or not yet available.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:NI:NA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:NIntegrity
None
A:HAvailability
High
Open in CVSS calculator →

Weaknesses

CWE-835

Affected Products

Siemens
commercial·DEaka siemens ag
capital vstar
ICS / OT / IoT
Nucleus NET
ICS / OT / IoT
Nucleus ReadyStart V3
ICS / OT / IoT
Nucleus ReadyStart V4
ICS / OT / IoT
Nucleus Source Code
ICS / OT / IoT
Capital Embedded AR Classic 431-422
ICS / OT / IoT
Capital Embedded AR Classic R20-11
ICS / OT / IoT
and 4 more affected products View all →

Exploitability

Official Patch Available
Is your org exposed to CVE-2021-25664?We can run the check for you — a free external exposure review, no install. Check my exposure

Attack Graph

Products CVE Techniques Tactics

Click technique nodes for MITRE ATT&CK details · drag to pan · Ctrl/⌘ + scroll to zoom, or go fullscreen.

MITRE ATT&CK

1 technique
Impact
View detailed technique mapping

References

https://cert-portal.siemens.com/productcert/csaf/ssa-248289.json
cert-portal.siemens.com
https://cert-portal.siemens.com/productcert/html/ssa-248289.html
cert-portal.siemens.com
https://raw.githubusercontent.com/cisagov/CSAF/develop/csaf_files/OT/white/2021/icsa-21-103-05.json
raw.githubusercontent.com
and 9 more references View all →

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