CVE-2020-9967Public exploitNetwork attack vector

Kernel memory corruption via 6LoWPAN length underflow

Published Apr 2, 2021 · Updated Aug 4, 2024

Kernel memory corruption in Apple operating systems allows remote attackers to crash devices or corrupt kernel memory via crafted 6LoWPAN frames. The sixlowpan_input path trusts an attacker-controlled frame length, ignores parser failure, and lets sixxlowpan_uncompress pass an underflowed size to memmove. Reachability requires a configured 6LoWPAN interface; triggering the flaw can terminate the system or overwrite kernel memory.

CVSS severity7.8
High
EPSS probability2.32%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Kernel memory corruption in Apple operating systems allows remote attackers to crash devices or corrupt kernel memory via crafted 6LoWPAN frames. The sixlowpan_input path trusts an attacker-controlled frame length, ignores parser failure, and lets sixxlowpan_uncompress pass an underflowed size to memmove. Reachability requires a configured 6LoWPAN interface; triggering the flaw can terminate the system or overwrite kernel memory.

The record

CVE
CVE-2020-9967
Published
Apr 2, 2021
Updated
Aug 4, 2024
Vendor
Apple
Product
iOS and iPadOS
Classifications
CWE-787, T1499
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 2, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=unspecified <14.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Apple · iOS and iPadOSversion=unspecified <14.0
Apple · tvOSversion=unspecified <14.0
Apple · macOSversion=unspecified <11.0; version=unspecified <11.1
Apple · watchOSversion=unspecified <7.0

Published CVSS scores

7.8NIST NVDCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
9.3NIST NVDAV:N/AC:M/Au:N/C:C/I:C/A:C

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-787Out-of-bounds Write
T1499Endpoint Denial of Service

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo