How severe is CVE-2018-18558?

CVE-2018-18558 has a CVSS 3.x base score of 6.4, rated medium severity. It is exploitable over physical access with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2018-18558 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (31st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-18558?

CVE-2018-18558 affects Espressif Esp-idf. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-18558?

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

When was CVE-2018-18558 published?

CVE-2018-18558 was published on 2019-05-13 and last updated on 2026-06-17.

CVE-2018-18558

CVE-2018-18558 is a medium-severity vulnerability in Espressif Esp-idf with a CVSS 3.x base score of 6.4. 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 6.4)
CVSS v2: 6.9
EPSS exploit prediction: 0% (31st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Espressif Esp-idf
Published: 2019-05-13
Last modified: 2026-06-17

Description

An issue was discovered in Espressif ESP-IDF 2.x and 3.x before 3.0.6 and 3.1.x before 3.1.1. Insufficient validation of input data in the 2nd stage bootloader allows a physically proximate attacker to bypass secure boot checks and execute arbitrary code, by crafting an application binary that overwrites a bootloader code segment in process_segment in components/bootloader_support/src/esp_image_format.c. The attack is effective when the flash encryption feature is not enabled, or if the attacker finds a different vulnerability that allows them to write this binary to flash memory.

Frequently asked questions

What is CVE-2018-18558?: An issue was discovered in Espressif ESP-IDF 2.x and 3.x before 3.0.6 and 3.1.x before 3.1.1. Insufficient validation of input data in the 2nd stage bootloader allows a physically proximate attacker to bypass secure boot checks and execute arbitrary code, by crafting an application binary that overwrites a bootloader code segment in process_segment in components/bootloader_support/src/esp_image_format.c. The attack is effective when the flash encryption feature is not enabled, or if the attacker finds a different vulnerability that allows them to write this binary to flash memory.
How severe is CVE-2018-18558?: CVE-2018-18558 has a CVSS 3.x base score of 6.4, rated medium severity. It is exploitable over physical access with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2018-18558 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (31st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-18558?: CVE-2018-18558 affects Espressif Esp-idf. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-18558?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2018-18558 published?: CVE-2018-18558 was published on 2019-05-13 and last updated on 2026-06-17.

References

Affected products (1)

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

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