Read the docs
TI-2021-02331 Aliases CVE-2021-3329GHSA-gmxc-973j-62f2

DOS: Incorrect handling of the initial HCI ACL_MTU handshake packet leads to crash of bluetooth host layer

Priority MEDIUM 42CWE-703Published · Updated

Key facts

Attack vector
Adjacent network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
Low · High · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA.

Summary

Lack of proper validation in HCI Host stack initialization can cause a crash of the bluetooth stack

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00616 49th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
zephyrprojectzephyrup to v2.4—No fix listedCNA
  • zephyr Vendorzephyrproject Affected up to v2.4 Fixed in — No fix listed CNA

CPE configurations NVD · 4

CPEVersionsRoleVendor
cpe:2.3:o:zephyrproject:zephyr:2.4.0:-:*:*:*:*:*:*2.4.0Vulnerablezephyrproject
cpe:2.3:o:zephyrproject:zephyr:2.4.0:rc1:*:*:*:*:*:*2.4.0 rc1Vulnerablezephyrproject
cpe:2.3:o:zephyrproject:zephyr:2.4.0:rc2:*:*:*:*:*:*2.4.0 rc2Vulnerablezephyrproject
cpe:2.3:o:zephyrproject:zephyr:2.4.0:rc3:*:*:*:*:*:*2.4.0 rc3Vulnerablezephyrproject
  • cpe:2.3:o:zephyrproject:zephyr:2.4.0:-:*:*:*:*:*:* Versions 2.4.0 Vulnerable ·zephyrproject
  • cpe:2.3:o:zephyrproject:zephyr:2.4.0:rc1:*:*:*:*:*:* Versions 2.4.0 rc1 Vulnerable ·zephyrproject
  • cpe:2.3:o:zephyrproject:zephyr:2.4.0:rc2:*:*:*:*:*:* Versions 2.4.0 rc2 Vulnerable ·zephyrproject
  • cpe:2.3:o:zephyrproject:zephyr:2.4.0:rc3:*:*:*:*:*:* Versions 2.4.0 rc3 Vulnerable ·zephyrproject

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-3329
  2. 2026-10-03 Alias added: GHSA-gmxc-973j-62f2

References

Exploit 1

  • TI-2026-04422 Out-of-bounds read/write in HTTP WebSocket upgrade via non-null-terminated Sec-WebSocket-Key CVSS 3.1CRITICAL 9.8
  • TI-2026-01361 dns: memory‑safety issue in the DNS name parser CVSS 3.1CRITICAL 9.8
  • TI-2026-09174 Unterminated URI buffer causes out-of-bounds read in LwM2M firmware pull (Package URI) CVSS 3.1CRITICAL 9.1
  • TI-2026-09168 Stack buffer overflow in `net_ipaddr_parse()` IPv4 address-with-port parsing in `subsys/net/ip/utils.c` CVSS 3.1CRITICAL 9.8
  • TI-2024-09625 net: lib: http_server: Buffer Under-read CVSS 3.1HIGH 8.6
  • TI-2021-02863 Usb bluetooth device ACL read cb buffer overflow CVSS 3.1CRITICAL 9.6
See all 196 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences