CVE-2021-3966
CVE-2021-3966 is a critical-severity vulnerability in Zephyrproject Zephyr with a CVSS 3.x base score of 9.6. 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-120.
Key facts
- Severity: Critical (CVSS 3.x base score 9.6)
- EPSS exploit prediction: 0% (38th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-120
- Affected product: Zephyrproject Zephyr
- Published:
- Last modified:
Description
usb device bluetooth class includes a buffer overflow related to implementation of net_buf_add_mem.
Frequently asked questions
- What is CVE-2021-3966?
- usb device bluetooth class includes a buffer overflow related to implementation of net_buf_add_mem.
- How severe is CVE-2021-3966?
- CVE-2021-3966 has a CVSS 3.x base score of 9.6, rated critical severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity high, and availability high.
- Is CVE-2021-3966 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (38th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-3966?
- CVE-2021-3966 affects Zephyrproject Zephyr. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-3966?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
- When was CVE-2021-3966 published?
- CVE-2021-3966 was published on 2023-01-11 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:o:zephyrproject:zephyr:*:*:*:*:*:*:*:*
More vulnerabilities in Zephyrproject Zephyr
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- CVE-2018-1000800 — Critical (CVSS 9.8): zephyr-rtos version 1.12.0 contains a NULL base pointer reference vulnerability in sys_ring_buf_put(),…
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