How severe is CVE-2020-13594?

CVE-2020-13594 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2020-13594 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-13594?

CVE-2020-13594 affects Espressif Esp-idf. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-13594?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2020-13594 published?

CVE-2020-13594 was published on 2020-08-31 and last updated on 2026-06-17.

CVE-2020-13594

CVE-2020-13594 is a medium-severity vulnerability in Espressif Esp-idf with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 3.3
EPSS exploit prediction: 1% (51st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Espressif Esp-idf
Published: 2020-08-31
Last modified: 2026-06-17

Description

The Bluetooth Low Energy (BLE) controller implementation in Espressif ESP-IDF 4.2 and earlier (for ESP32 devices) does not properly restrict the channel map field of the connection request packet on reception, allowing attackers in radio range to cause a denial of service (crash) via a crafted packet.

Frequently asked questions

What is CVE-2020-13594?: The Bluetooth Low Energy (BLE) controller implementation in Espressif ESP-IDF 4.2 and earlier (for ESP32 devices) does not properly restrict the channel map field of the connection request packet on reception, allowing attackers in radio range to cause a denial of service (crash) via a crafted packet.
How severe is CVE-2020-13594?: CVE-2020-13594 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2020-13594 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-13594?: CVE-2020-13594 affects Espressif Esp-idf. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-13594?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-13594 published?: CVE-2020-13594 was published on 2020-08-31 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:espressif:esp-idf:*:*:*:*:*:*:*:*

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