CVE-2021-1780

Denial of service via uninitialized Bluetooth memory

Published Apr 2, 2021 · Updated Aug 3, 2024

Improper memory initialization in Bluetooth in Apple iOS and iPadOS before 14.4 allows local users to interrupt service. The Bluetooth component leaves memory improperly initialized and handles the resulting state without sufficient memory safeguards. High privileges are required, and Apple has not disclosed whether the resulting denial of service causes a hang, crash, reboot, or shutdown.

CVSS severity4.4
Medium
EPSS probability0.25%
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

Improper memory initialization in Bluetooth in Apple iOS and iPadOS before 14.4 allows local users to interrupt service. The Bluetooth component leaves memory improperly initialized and handles the resulting state without sufficient memory safeguards. High privileges are required, and Apple has not disclosed whether the resulting denial of service causes a hang, crash, reboot, or shutdown.

The record

CVE
CVE-2021-1780
Published
Apr 2, 2021
Updated
Aug 3, 2024
Vendor
Apple
Product
iOS and iPadOS
Classifications
CWE-665, T1499
Attack vector
local
Privileges
admin

Timeline

How it unfolded

  1. Apr 2, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 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 <14.4

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

Apple · iOS and iPadOSversion=unspecified <14.4

Published CVSS scores

4.9NIST NVDAV:L/AC:L/Au:N/C:N/I:N/A:C
4.4NIST NVDCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H

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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-665Improper Initialization
T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

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