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CVE-2020-35685

Published: Aug 19, 2021Updated: Nov 21, 2024 Sources: CVE List NVD BDU csafCWE-330
NVD MITRE
9.1CVSSCRITICAL
EPSS Score
2.1%
Top 21.3%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch 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.)

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
Open in CVSS calculator →

Weaknesses

CWE-330

Affected Products

n/an/a
nichestackhcc-embedded
Embedded
Operating Systems / rtos-embedded-os
sentron 3wa com190 firmwaresiemens
On-prem
Enterprise Software / collaboration-groupware
sentron 3wl com35 firmwaresiemens
On-prem
Enterprise Software / collaboration-groupware
NicheLiteHCC Embedded
Embedded
ICS / OT / IoT / medical-device
hcc-embeddedcommercialOperating Systemsaka nichestack, interniche, nichestack tcp/ip
siemenscommercialDEEnterprise Softwareaka siemens ag
hcc embeddedcommercialICS / OT / IoTaka interniche, nichelite
and 1 more affected products View all →

Attack Graph

Products CVE Techniques Tactics

Click technique nodes to view MITRE ATT&CK details. Scroll to zoom, drag to pan.

Exploitability

Official Patch Available
Workaround Available

MITRE ATT&CK

1 technique
Credential Access
View detailed technique mapping

References

https://www.hcc-embedded.com
hcc-embedded.com
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
and 30 more references View all →

Timeline

Published
Aug 19, 2021
Last Updated
Nov 21, 2024

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