Zephyr
CVE-2021-3320
HIGH
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A10:2025 - Mishandling of Exceptional Conditions
ASVS 5.0
V16 - Security Logging and Error Handling Null pointer safety, defensive checks
MITRE ATT&CK
1 technique across 1 tactic: Impact The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | CVSS score of 7.5 (HIGH). Attack characteristics: network attack vector, low complexity, no privileges required, no user interaction not required. |
| Exploit ScenarioDerived | A remote attacker could crash the application by dereferencing a null pointer by sending crafted requests to the affected application. No authentication is required to exploit this vulnerability. |
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Alert meAnalysisAI
Type Confusion in 802154 ACK Frames Handling. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
RemediationAI
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Check pointers before dereferencing. Use static analysis tools to detect null pointer paths.
Affects your stack
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Technical ContextAI · show details
This vulnerability is classified as NULL Pointer Dereference (CWE-476), which allows attackers to crash the application by dereferencing a null pointer. Type Confusion in 802154 ACK Frames Handling. Zephyr versions >= v2.4.0 contain NULL Pointer Dereference (CWE-476). For more information, see https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-27r3-rxch-2hm7 Affected products include: Zephyrproject Zephyr.
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionNVD
Type Confusion in 802154 ACK Frames Handling. Zephyr versions >= v2.4.0 contain NULL Pointer Dereference (CWE-476). For more information, see https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-27r3-rxch-2hm7
Threat Intelligence Overview
NVD
CVE.org
EPSS
GitHub
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
A null pointer dereference occurs when a program attempts to access memory through a pointer that has been set to NULL (address 0x0).
Denial of Service attacks render applications or systems unavailable by overwhelming resources or triggering failure conditions.
Affected Products (CPE)NVD
Potential off-by-one buffer overflow vulnerability in the Zephyr fuse file system. Rated critical severity (CVSS 10.0),
An out-of-bounds write in the Zephyr RTOS DNS resolver (dns_unpack_name()) lets a crafted DNS response corrupt memory on
Possible variant of CVE-2021-3434 in function le_ecred_reconf_req. Rated critical severity (CVSS 9.8), this vulnerabilit
Unchecked user input length in /subsys/net/l2/wifi/wifi_shell.c can cause buffer overflows. Rated critical severity (CVS
Potential buffer overflow vulnerability in the Zephyr CAN bus subsystem. Rated critical severity (CVSS 9.8), this vulner
Integer Underflow in 6LoWPAN IPHC Header Uncompression in Zephyr. Rated critical severity (CVSS 9.8), this vulnerability
Buffer overflow in Zephyr USB DFU DNLOAD. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable
DOS: Incorrect 802154 Frame Validation for Omitted Source / Dest Addresses. Rated critical severity (CVSS 9.8), this vul
zephyr-rtos version 1.12.0 contains a NULL base pointer reference vulnerability in sys_ring_buf_put(), sys_ring_buf_get(
Potential buffer overflow vulnerabilities n the Zephyr Bluetooth subsystem. Rated critical severity (CVSS 9.6), this vul
The documentation specifies that the BT_GATT_PERM_READ_LESC and BT_GATT_PERM_WRITE_LESC defines for a Bluetooth characte
Potential buffer overflows in the Bluetooth subsystem due to asserts being disabled in /subsys/bluetooth/host/hci_core.c
Exploit-DB