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CVE-2021-25663

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

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 IPv6 headers does not check the lengths of extension header options, allowing attackers to put this function into an infinite loop with crafted length values.

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
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Weaknesses

CWE-835

Affected Products

Siemens
commercial·DEaka siemens ag
Capital Embedded AR Classic 431-422
ICS / OT / IoT
Capital Embedded AR Classic R20-11
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 vstar
ICS / OT / IoT
nucleus readystart
ICS / OT / IoT
and 2 more affected products View all →

Exploitability

Official Patch Available
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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/pdf/ssa-248289.pdf
cert-portal.siemens.com
https://us-cert.cisa.gov/ics/advisories/icsa-21-103-05
us-cert.cisa.gov
https://cert-portal.siemens.com/productcert/html/ssa-248289.html
cert-portal.siemens.com
and 9 more references View all →

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