Security readout for executives and security teams
This vulnerability can let malformed IEEE 802.15.4 ACK frame handling crash affected Zephyr-based systems. The documented impact is availability, not data theft or tampering. Business urgency depends on whether products use Zephyr with 802.15.4 networking in reliability-sensitive environments. Exposure is most likely in embedded or IoT products built on Zephyr v2.4.0 or later where 802.15.4 networking is enabled. The bundle lists Zephyr v2.4.0 in affected data, while the description says versions >= v2.4.0; verify exact affected ranges against the GitHub advisory. Treat as a moderate availability risk. Prioritize products using Zephyr and 802.15.4 in operationally important deployments, but do not escalate as data breach risk based on the supplied evidence. Mitigation focus: Check the Zephyr GitHub advisory for fixed versions or vendor guidance.; Inventory products using zephyrproject-rtos/zephyr and 802.15.4 networking.; Prioritize remediation for devices where crashes affect operations or safety..
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
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ATT&CK lookup starting points
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CWE-476: Exact CWE lookup
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Open ATT&CK lookupCVE-2021-3320 mapping review
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Open ATT&CK lookup- Severity
- Medium
- CVSS
- 5.9 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
CNA and ADP enrichment extracted from CVE v5
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CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H2.23.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
5.9MediumVector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Source materials
- CVE List V5 sourceCVE List V5
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
NULL Pointer Dereference
NULL Pointer Dereference represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.