What’s Vulnerable › Vulnerabilities

CVE-2020-10021: Out-of-bounds write in USB Mass Storage with unaligned sizes

• Severity: high (CVSS 7.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.4% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2020-05-11 · updated 2026-06-17
• Weakness: CWE-787

Description

Out-of-bounds Write in the USB Mass Storage memoryWrite handler with unaligned Sizes See NCC-ZEP-024, NCC-ZEP-025, NCC-ZEP-026 This issue affects: zephyrproject-rtos zephyr version 1.14.1 and later versions. version 2.1.0 and later versions.

Affected products

• zephyrproject zephyr: through 1.14.1; from 2.1.0 before 2.2.0 — fixed in 2.2.0

How to fix

Upgrade to a fixed version: zephyrproject zephyr 2.2.0. Check the vendor advisory for mitigations.

References

• https://docs.zephyrproject.org/latest/security/vulnerabilities.html#cve-2020-10021
• https://github.com/zephyrproject-rtos/zephyr/pull/23240
• https://github.com/zephyrproject-rtos/zephyr/pull/23455
• https://github.com/zephyrproject-rtos/zephyr/pull/23456
• https://zephyrprojectsec.atlassian.net/browse/ZEPSEC-26
• https://docs.zephyrproject.org/latest/security/vulnerabilities.html#cve-2020-10021
• https://github.com/zephyrproject-rtos/zephyr/pull/23240
• https://github.com/zephyrproject-rtos/zephyr/pull/23455
• https://github.com/zephyrproject-rtos/zephyr/pull/23456
• https://zephyrprojectsec.atlassian.net/browse/ZEPSEC-26

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