Ethernut NutOS 5.1 TCP Initial Sequence Number random values

CVSS Meta Temp Score
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CTI Interest Score
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3.7$0-$5k0.00

Summaryinfo

A vulnerability classified as problematic was found in Ethernut NutOS 5.1. This affects an unknown part of the component TCP Initial Sequence Number Handler. Executing a manipulation can lead to random values. This vulnerability appears as CVE-2020-27213. The attack may be performed from remote. There is no available exploit.

Detailsinfo

A vulnerability was found in Ethernut NutOS 5.1. It has been declared as problematic. This vulnerability affects an unknown function of the component TCP Initial Sequence Number Handler. The manipulation with an unknown input leads to a random values vulnerability. The CWE definition for the vulnerability is CWE-330. The product uses insufficiently random numbers or values in a security context that depends on unpredictable numbers. As an impact it is known to affect integrity. CVE summarizes:

An issue was discovered in Ethernut Nut/OS 5.1. 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. While the ISN generator seems to adhere to RFC 793 (where a global 32-bit counter is incremented roughly every 4 microseconds), proper ISN generation should aim to follow at least the specifications outlined in RFC 6528.

The weakness was presented 10/10/2023. The advisory is available at lists.egnite.de. This vulnerability was named CVE-2020-27213 since 10/19/2020. The technical details are unknown and an exploit is not available. This vulnerability is assigned to T1600.001 by the MITRE ATT&CK project.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 3.7
VulDB Meta Temp Score: 3.7

VulDB Base Score: 3.7
VulDB Temp Score: 3.7
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Random values
CWE: CWE-330 / CWE-310
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

10/19/2020 🔍
10/10/2023 +1086 days 🔍
10/10/2023 +0 days 🔍
10/10/2023 +0 days 🔍

Sourcesinfo

Advisory: lists.egnite.de
Status: Not defined

CVE: CVE-2020-27213 (🔍)
GCVE (CVE): GCVE-0-2020-27213
GCVE (VulDB): GCVE-100-241738

Entryinfo

Created: 10/10/2023 19:26
Changes: 10/10/2023 19:26 (38)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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