CVE-2021-30983Known exploitation

Kernel code execution via IOMobileFrameBuffer buffer overflow

Published Aug 24, 2021 · Updated Oct 21, 2025

Buffer overflow in Apple iOS and iPadOS before 15.2 allows attackers to execute arbitrary code with kernel privileges. IOMobileFrameBuffer fails to keep a memory operation within its buffer, although Apple has not disclosed the specific operation or input that overruns it. Attackers must first obtain application execution on the device; successful exploitation grants kernel-level control.

CVSS severity7.8
High
EPSS probability2.92%
Next 30 days · Sep 16, 2026
Known exploitationReported
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Buffer overflow in Apple iOS and iPadOS before 15.2 allows attackers to execute arbitrary code with kernel privileges. IOMobileFrameBuffer fails to keep a memory operation within its buffer, although Apple has not disclosed the specific operation or input that overruns it. Attackers must first obtain application execution on the device; successful exploitation grants kernel-level control.

The record

CVE
CVE-2021-30983
Published
Aug 24, 2021
Updated
Oct 21, 2025
Vendor
Apple
Product
iOS and iPadOS
Classifications
CWE-120, T1404
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 24, 2021CVE publishedPublication date reported by the CVE source.
  2. Oct 21, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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

  1. Affected versionversion=unspecified <15.2

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Apple · iOS and iPadOSversion=unspecified <15.2

Published CVSS scores

7.8CISA-ADPCVSS: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
7.8NIST NVDCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/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.

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No observations available

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

Weakness, pattern, technique

CWE-120Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
T1404Exploitation for Privilege Escalation

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.

Reported exploitation

Technologies

Your stack

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Your stack

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