CVE-2020-11957

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.

Published: 2020-06-09 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2020-11957 is rated Moderate Risk (41/100): CVSS High severity, with low exploitation likelihood (EPSS 0.39%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2020-11957

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.22% 0.39% +0.18%
2 2026-04-16 0.05% 0.22% +0.16%
3 2023-03-07 — 0.05% —

Full EPSS history (7 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-11957

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:A)
Attacker has to be nearby on the network—same office, same link, that vibe—not the whole wide internet.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.6 5.9 [email protected]
5.4 2.0 MEDIUM
AV:A/AC:M/Au:N/C:P/I:P/A:P Click to expand
Access vector (AV:A)
Requires access to an adjacent network segment.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 5.5 6.4 [email protected]

Weakness enumeration for CVE-2020-11957

Affected software / configurations for CVE-2020-11957

Vendor Product Version Raw CPE
cypress psoc_4.2_ble < 3.64 cpe:2.3:a:cypress:psoc_4.2_ble:*:*:*:*:*:*:*:*

References for CVE-2020-11957

URL Tags
https://www.cypress.com/file/504466/download Product Vendor Advisory
cvelogic Threat Intelligence