CVE-2020-26558: bluetooth bluetooth_core_specification Improper Authentication

Modified

AliasesRHSA-2021:4432UBUNTU-CVE-2020-26558DEBIAN-CVE-2020-26558

Published 24-05-2021Last modified 04-11-2025

Vulnerability summary

CVE-2020-26558 is a medium (CVSS 4.3) Improper Authentication vulnerability in bluetooth bluetooth_core_specification. EPSS estimates a 0.87% chance of exploitation in the next 30 days, higher than 58.9% of scored vulnerabilities.

Priority

Routine

Not severe (CVSS 4.2, adjacent network); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?

CVSS score

4.3/10

010

Medium · v2.0 (NVD)

EPSS score

0.87%

0%100%

Low · 0.00 pp in 30 days

KEVNot listedNot listed by any tracked catalog.

RansomwareNot flaggedNo ransomware use recorded.

Public exploits0No public exploits recorded

Timeline

24-05-2021
PublishedVulnerability first disclosed.
04-11-2025
Last modifiedVulnerability information updated.

Description

Bluetooth LE and BR/EDR secure pairing in Bluetooth Core Specification 2.1 through 5.2 may permit a nearby man-in-the-middle attacker to identify the Passkey used during pairing (in the Passkey authentication procedure) by reflection of the public key and the authentication evidence of the initiating device, potentially permitting this attacker to complete authenticated pairing with the responding device using the correct Passkey for the pairing session. The attack methodology determines the Passkey value one bit at a time.

CVSS metrics

5 scores · 4 sources · 2 versions

v3.14.2v2.04.3

EPSS trend

Probability

0.87%

Chance of exploitation in the next 30 days

Percentile

59%

Versus all other CVEs

30-day change

No change 0.00 pp

From 0.87% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs

CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

CWE-287Improper AuthenticationWhen an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.

Affected systems

Version check

Known conditions: adjacent network, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.

Ubuntu61 products

bluez< 5.37-0ubuntu5.3+esm1 | < 5.48-0ubuntu3.5 | < 5.53-0ubuntu3.2
linuxAll versions (No fix recorded) | < 4.4.0-219.252 | < 4.15.0-151.157 | < 5.4.0-80.90
linux-aws< 4.4.0-1099.104 | < 4.4.0-1135.149 | < 4.15.0-1109.116 | < 5.4.0-1054.57
linux-aws-5.0All versions (No fix recorded)
linux-aws-5.11< 5.11.0-1016.17~20.04.1

linux-aws-5.3All versions (No fix recorded)
linux-aws-5.4< 5.4.0-1054.57~18.04.1
linux-aws-5.8< 5.8.0-1042.44~20.04.1
linux-aws-fips< 4.15.0-2051.53 | All versions (No fix recorded) | < 5.4.0-1069.73+fips2
linux-aws-hwe< 4.15.0-1109.116~16.04.1
linux-azure< 4.15.0-1121.134~14.04.1 | < 4.15.0-1121.134~16.04.1 | All versions (No fix recorded) | < 5.4.0-1055.57
linux-azure-4.15< 4.15.0-1121.134
linux-azure-5.11< 5.11.0-1013.14~20.04.1
linux-azure-5.3All versions (No fix recorded)
linux-azure-5.4< 5.4.0-1055.57~18.04.1
linux-azure-5.8< 5.8.0-1040.43~20.04.1
linux-azure-edgeAll versions (No fix recorded)
linux-azure-fde-5.15< 5.15.0-1114.123~20.04.1
linux-azure-fips< 4.15.0-2033.37 | All versions (No fix recorded) | < 5.4.0-1073.76+fips1
linux-bluefield< 5.4.0-1016.19
linux-dell300x< 4.15.0-1027.32
linux-fips< 4.4.0-1069.75 | All versions (No fix recorded) | < 4.15.0-1066.75 | < 5.4.0-1031.36
linux-gcp< 4.15.0-1106.120~16.04.1 | All versions (No fix recorded) | < 5.4.0-1049.53
linux-gcp-4.15< 4.15.0-1106.120
linux-gcp-5.11< 5.11.0-1017.19~20.04.1
linux-gcp-5.3All versions (No fix recorded)
linux-gcp-5.4< 5.4.0-1049.53~18.04.1
linux-gcp-5.8< 5.8.0-1039.41
linux-gcp-edgeAll versions (No fix recorded)
linux-gcp-fips< 4.15.0-2016.18 | All versions (No fix recorded) | < 5.4.0-1067.71~20.04.1
linux-gke< 5.4.0-1049.52
linux-gke-4.15All versions (No fix recorded)
linux-gke-5.4< 5.4.0-1049.52~18.04.1
linux-gkeop< 5.4.0-1021.22
linux-gkeop-5.4< 5.4.0-1021.22~18.04.1
linux-hwe< 4.15.0-151.157~16.04.1 | All versions (No fix recorded)
linux-hwe-5.11< 5.11.0-34.36~20.04.1
linux-hwe-5.4< 5.4.0-80.90~18.04.1
linux-hwe-5.8All versions (No fix recorded)
linux-hwe-edgeAll versions (No fix recorded)
linux-intel-iot-realtimeAll versions (No fix recorded)
linux-kvm< 4.4.0-1100.109 | < 4.15.0-1097.99 | < 5.4.0-1044.46
linux-lts-xenial< 4.4.0-219.252~14.04.1
linux-oemAll versions (No fix recorded)
linux-oem-5.10< 5.10.0-1032.33
linux-oem-5.6All versions (No fix recorded)
linux-oracle< 4.15.0-1078.86~16.04.1 | < 4.15.0-1078.86 | < 5.4.0-1052.56
linux-oracle-5.0All versions (No fix recorded)
linux-oracle-5.11< 5.11.0-1016.17~20.04.1
linux-oracle-5.3All versions (No fix recorded)
linux-oracle-5.4< 5.4.0-1052.56~18.04.1
linux-oracle-5.8< 5.8.0-1038.39~20.04.1
linux-raspi< 5.4.0-1041.45
linux-raspi-5.4< 5.4.0-1041.45~18.04.1
linux-raspi-realtimeAll versions (No fix recorded)
linux-raspi2< 4.15.0-1092.98 | All versions (No fix recorded)
linux-realtimeAll versions (No fix recorded)
linux-riscvAll versions (No fix recorded)
linux-riscv-5.11< 5.11.0-1017.18~20.04.1
linux-riscv-5.8All versions (No fix recorded)
linux-snapdragon< 4.15.0-1109.118