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TI-2021-02419 Aliases CVE-2021-3455

Use after free in zephyrproject zephyr

Priority LOW 35CWE-416Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-416 and the CVSS impact.

Summary

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

Why it matters now

EPSS 0.01106 66th 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

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
zephyrprojectzephyr2.4.0 and later; 2.5.0 and later—No fix listedCNA
  • zephyr Vendorzephyrproject Affected 2.4.0 and later; 2.5.0 and later Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:o:zephyrproject:zephyr:*:*:*:*:*:*:*:*2.4.0 to before 2.6.0Vulnerablezephyrproject
  • cpe:2.3:o:zephyrproject:zephyr:*:*:*:*:*:*:*:* Versions 2.4.0 to before 2.6.0 Vulnerable ·zephyrproject

Remediation

No fixed version listed by the sources yet.

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    zephyrproject-rtos zephyr unspecified

    2 records Highest priority Priority LOW 2 LOW

    Other records, highest priority first

    • TI-2021-02418 Reachable assertion in zephyrproject zephyrPriority LOW 35
    Show all 2 records →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-3455

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