7.5

CVE-2020-11957: cypress psoc_4.2_ble Insufficient Entropy

CVSS: 7.5v3.1HighModified
Published 09-06-2020Last modified 04-08-2024
Open JSON

Vulnerability summary

CVE-2020-11957 is a high (CVSS 7.5) Insufficient Entropy vulnerability in cypress psoc_4.2_ble. EPSS estimates a 0.39% chance of exploitation in the next 30 days, higher than 32% of scored vulnerabilities.

Overall risk
30/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.5/10
010
High · v3.1 (NVD)
EPSS score
0.39%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 09-06-2020
    PublishedVulnerability first disclosed.
  2. 04-08-2024
    Last modifiedVulnerability information updated.

Description

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.

CVSS metrics

2 scores · 1 source · 2 versions

EPSS trend

Probability

0.39%

Chance of exploitation in the next 30 days

Percentile

32%

Versus all other CVEs

30-day change

0.00 pp

From 0.39% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.39%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Cypress1 product

1 vendor · 1 product

References

1 links