CVE-2020-35685

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 v3.0 9.1 CRITICAL
CVSS v2.0 6.4 MEDIUM

9.1^/10

CVSS v3.0 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

6.4^/10

CVSS v2.0 : MEDIUM

Vector : AV:N/AC:L/Au:N/C:P/I:P/A:N

Exploitability : 10.0 / Impact : 4.9

Access Vector NETWORK

Access Complexity LOW

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact PARTIAL

Availability Impact NONE

References

Link	Resource
https://cert-portal.siemens.com/productcert/pdf/ssa-789208.pdf	Mitigation Third Party Advisory
https://www.hcc-embedded.com	Product
https://www.kb.cert.org/vuls/id/608209	Third Party Advisory US Government Resource
https://www.forescout.com/blog/new-critical-operational-technology-vulnerabilities-found-on-nichestack/	Mitigation Third Party Advisory

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Configurations

Configuration 1 (hide)

cpe:2.3:a:hcc-embedded:nichestack:3.0:*:*:*:*:*:*:*

Configuration 2 (hide)

AND

cpe:2.3:o:siemens:sentron_3wa_com190_firmware:*:*:*:*:*:*:*:*

cpe:2.3:h:siemens:sentron_3wa_com190:-:*:*:*:*:*:*:*

Configuration 3 (hide)

AND

cpe:2.3:o:siemens:sentron_3wl_com35_firmware:*:*:*:*:*:*:*:*

cpe:2.3:h:siemens:sentron_3wl_com35:-:*:*:*:*:*:*:*

Information

Published : 2021-08-19 05:15

Updated : 2021-08-26 11:21

NVD link : CVE-2020-35685

Mitre link : CVE-2020-35685

JSON object : View

CWE

CWE-330

Use of Insufficiently Random Values

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Products Affected

hcc-embedded

nichestack

siemens

sentron_3wa_com190
sentron_3wa_com190_firmware
sentron_3wl_com35_firmware
sentron_3wl_com35

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