CVE-2021-3434
CVE-2021-3434 is a medium-severity vulnerability in Zephyrproject Zephyr with a CVSS 3.x base score of 4.9. 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-787.
Key facts
- Severity: Medium (CVSS 3.x base score 4.9)
- CVSS v2: 4.6
- EPSS exploit prediction: 0% (10th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-787
- Affected product: Zephyrproject Zephyr
- Published:
- Last modified:
Description
Stack based buffer overflow in le_ecred_conn_req(). Zephyr versions >= v2.5.0 Stack-based Buffer Overflow (CWE-121). For more information, see https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-8w87-6rfp-cfrm
Frequently asked questions
- What is CVE-2021-3434?
- Stack based buffer overflow in le_ecred_conn_req(). Zephyr versions >= v2.5.0 Stack-based Buffer Overflow (CWE-121). For more information, see https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-8w87-6rfp-cfrm
- How severe is CVE-2021-3434?
- CVE-2021-3434 has a CVSS 3.x base score of 4.9, rated medium severity. It is exploitable over local access with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.
- Is CVE-2021-3434 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (10th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-3434?
- CVE-2021-3434 affects Zephyrproject Zephyr. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-3434?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2021-3434 published?
- CVE-2021-3434 was published on 2022-06-28 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:o:zephyrproject:zephyr:*:*:*:*:*:*:*:*
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