How severe is CVE-2021-34173?

CVE-2021-34173 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-34173 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (71st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-34173?

CVE-2021-34173 affects Espressif Esp32 Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-34173?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-34173 published?

CVE-2021-34173 was published on 2021-07-14 and last updated on 2026-06-17.

CVE-2021-34173

CVE-2021-34173 is a high-severity vulnerability in Espressif Esp32 Firmware with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 7.8
EPSS exploit prediction: 1% (71st percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Espressif Esp32 Firmware
Published: 2021-07-14
Last modified: 2026-06-17

Description

An attacker can cause a Denial of Service and kernel panic in v4.2 and earlier versions of Espressif esp32 via a malformed beacon csa frame. The device requires a reboot to recover.

Frequently asked questions

What is CVE-2021-34173?: An attacker can cause a Denial of Service and kernel panic in v4.2 and earlier versions of Espressif esp32 via a malformed beacon csa frame. The device requires a reboot to recover.
How severe is CVE-2021-34173?: CVE-2021-34173 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-34173 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (71st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-34173?: CVE-2021-34173 affects Espressif Esp32 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-34173?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-34173 published?: CVE-2021-34173 was published on 2021-07-14 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:espressif:esp32_firmware:*:*:*:*:*:*:*:*

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