VDB-156432 · CVE-2020-11957 · GCVE-0-2020-11957

Cypress PSoC Creator BLE 4.2 Pairing PRNG entropy

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
6.0	$0-$5k	0.00

Summaryinfo

A vulnerability labeled as critical has been found in Cypress PSoC Creator BLE 4.2. Affected by this issue is some unknown functionality of the component Pairing Handler. The manipulation results in entropy (PRNG). This vulnerability is reported as CVE-2020-11957. The attacker must have access to the local network to execute the attack. No exploit exists. The affected component should be upgraded.

Detailsinfo

A vulnerability, which was classified as critical, was found in Cypress PSoC Creator BLE 4.2. Affected is an unknown part of the component Pairing Handler. The manipulation with an unknown input leads to a entropy vulnerability (PRNG). CWE is classifying the issue as CWE-331. The product uses an algorithm or scheme that produces insufficient entropy, leaving patterns or clusters of values that are more likely to occur than others. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

The Bluetooth Low Energy implementation in Cypress PSoC Creator BLE 4.2 component versions before 3.64 generates a random number (Pairing Random) with significantly less entropy than the specified 128 bits during BLE pairing. This is the case for both authenticated and unauthenticated pairing with both LE Secure Connections as well as LE Legacy Pairing. A predictable or brute-forceable random number allows an attacker (in radio range) to perform a MITM attack during BLE pairing.

The weakness was disclosed 06/09/2020. This vulnerability is traded as CVE-2020-11957 since 04/20/2020. The exploitability is told to be difficult. The attack needs to be done within the local network. The exploitation doesn't require any form of authentication. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1600.001.

Upgrading eliminates this vulnerability.

VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Vendor

Cypress

Name

PSoC Creator BLE

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.2
VulDB Meta Temp Score: 6.1

VulDB Base Score: 5.0
VulDB Temp Score: 4.8
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.5
NVD Vector: 🔍

CVSSv2info

AV	AC	Au	C	I	A
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💳	💳	💳	💳	💳	💳
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Name: PRNG
Class: Entropy / PRNG
CWE: CWE-331 / CWE-330 / CWE-310
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Partially

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Timelineinfo

04/20/2020 🔍
06/09/2020 +50 days 🔍
06/10/2020 +1 days 🔍
10/23/2020 +135 days 🔍

Sourcesinfo

Status: Not defined
Confirmation: 🔍

CVE: CVE-2020-11957 (🔍)
GCVE (CVE): GCVE-0-2020-11957
GCVE (VulDB): GCVE-100-156432

Entryinfo

Created: 06/10/2020 11:31
Updated: 10/23/2020 16:37
Changes: 06/10/2020 11:31 (38), 06/10/2020 11:35 (17), 10/23/2020 16:37 (1)
Complete: 🔍
Cache ID: 216::103