---
id: "CVE-2021-30983"
kind: "vulnerability"
aliases: ["CVE-2021-30983"]
title: "A buffer overflow issue was addressed with improved memory handling"
severity: "critical"
cvss: 9.3
epss: 0.02923
exploited: true
status: "open"
category: "infrastructure"
products: [{"name": "Apple iOS and iPadOS", "fixed": [], "affected": "", "ecosystem": "vendor"}, {"name": "apple ipados", "fixed": ["15.2"], "affected": "< 15.2", "ecosystem": "vendor"}, {"name": "apple iphone os", "fixed": ["15.2"], "affected": "< 15.2", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["apple-devices", "exploited", "infrastructure", "ios", "ipados"]
not_affected_if: ["unpatched-version-not-running"]
published_at: "2021-08-24T19:15:23+00:00"
first_seen_at: "2026-10-23T19:11:52+00:00"
updated_at: "2026-10-23T22:29:04+00:00"
sources: [{"source": "kev", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2021-30983", "first_seen_at": "2026-10-23T19:11:52+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2021-30983", "first_seen_at": "2026-10-23T19:13:45+00:00"}, {"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-30983", "first_seen_at": "2026-10-23T22:29:04+00:00"}]
---

# A buffer overflow issue was addressed with improved memory handling

Apple iOS and iPadOS contain a buffer overflow that lets an app run code with kernel privileges. An attacker who runs a malicious app on the device gets full control of the operating system.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- vendor:Apple iOS and iPadOS affected ? fixed ?
- vendor:apple ipados affected < 15.2 fixed 15.2
- vendor:apple iphone os affected < 15.2 fixed 15.2

## How to check

Settings > General > About on the device, and compare the iOS or iPadOS version against Apple's security notes for this CVE.

## Fix

Update iOS and iPadOS to the fixed release listed in Apple's security notes for CVE-2021-30983.
CISA required action: apply updates per vendor instructions.

## Timeline

- 2026-10-23T19:11:52+00:00 kev https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2021-30983
- 2026-10-23T19:13:45+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2021-30983
- 2026-10-23T22:29:04+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2021-30983

## From the sources

Apple iOS and iPadOS contain a buffer overflow vulnerability that could allow an application to execute code with kernel privileges.

CISA required action: Apply updates per vendor instructions.

---

_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_