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CVE-2020-35685

Published: Aug 19, 2021Updated: Nov 21, 2024 Sources: CVE List NVD BDU csafCWE-330
9.1CRITICAL
NVD MITRE
EPSS Score
2.1%
Top 20.0%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
Not available

Description

An issue was discovered in HCC Nichestack 3.0. The code that generates Initial Sequence Numbers (ISNs) for TCP connections derives the ISN from an insufficiently random source. As a result, an attacker may be able to determine the ISN of current and future TCP connections and either hijack existing ones or spoof future ones. (Proper ISN generation should aim to follow at least the specifications outlined in RFC 6528.)

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:HI:HA:N
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:NAvailability
None
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Weaknesses

CWE-330

Affected Products

siemens
commercial·DEaka siemens ag
sentron 3wa com190 firmware
ICS / OT / IoT
sentron 3wl com35 firmware
ICS / OT / IoT
HCC Embedded
commercialaka nichelite, interniche
NicheLiteEmbedded
ICS / OT / IoT / medical-device
InterNicheEmbedded
ICS / OT / IoT / medical-device
hcc-embedded
commercialaka interniche, nichestack tcp/ip, nichestack
nichestackEmbedded
Operating Systems / rtos-embedded-os
and 1 more affected products View all →

Exploitability

Official Patch Available
Workaround 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
Credential Access
View detailed technique mapping

References

https://cert-portal.siemens.com/productcert/pdf/ssa-789208.pdf
cert-portal.siemens.com
https://www.forescout.com/blog/new-critical-operational-technology-vulnerabilities-found-on-nichestack/
forescout.com
https://www.hcc-embedded.com
hcc-embedded.com
and 30 more references View all →

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