CVE-2021-3455
CVE-2021-3455 is a medium-severity vulnerability in Zephyrproject Zephyr with a CVSS 3.x base score of 4.3. 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-416.
Key facts
- Severity: Medium (CVSS 3.x base score 4.3)
- CVSS v2: 5.0
- EPSS exploit prediction: 1% (61st percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-416
- Affected product: Zephyrproject Zephyr
- Published:
- Last modified:
Description
Disconnecting L2CAP channel right after invalid ATT request leads freeze. Zephyr versions >= 2.4.0, >= 2.5.0 contain Use After Free (CWE-416). For more information, see https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-7g38-3x9v-v7vp
Frequently asked questions
- What is CVE-2021-3455?
- Disconnecting L2CAP channel right after invalid ATT request leads freeze. Zephyr versions >= 2.4.0, >= 2.5.0 contain Use After Free (CWE-416). For more information, see https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-7g38-3x9v-v7vp
- How severe is CVE-2021-3455?
- CVE-2021-3455 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.
- Is CVE-2021-3455 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-3455?
- CVE-2021-3455 affects Zephyrproject Zephyr. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-3455?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2021-3455 published?
- CVE-2021-3455 was published on 2021-10-19 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:o:zephyrproject:zephyr:*:*:*:*:*:*:*:*
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