CVE-2023-42824
CVE-2023-42824 is a security flaw in Apple iOS and iPadOS, the operating system on iPhones and iPads. Someone who already has a foothold can use Apple iOS and iPadOS to take full control of the machine. The US Cybersecurity and Infrastructure Security Agency (CISA) added it to its catalog of flaws known to be used in attacks on 5 Oct 2023.[1]
Apple iOS and iPadOS is in things households have, such as phones, computers, browsers and everyday apps, so the fix matters at home as much as at work. Fixed in version 16.7 of iOS and iPadOS.
Description
CISA calls it a kernel privilege escalation in Apple iOS and iPadOS. In its words: “Apple iOS and iPadOS contain an unspecified vulnerability that allows for local privilege escalation.”[1]
The CVE record adds: “The issue was addressed with improved checks. This issue is fixed in iOS 16.7.1 and iPadOS 16.7.1. A local attacker may be able to elevate their privileges. Apple is aware of a report that this issue may have been actively exploited against versions of iOS before iOS 16.6.”[2]
It scores 7.8 out of 10 on the Common Vulnerability Scoring System, which rates it high, scored by NVD using CVSS 3.1.[2]
Affected versions
NVD’s record lists one fixed version: everything before it is affected.[2]
| Product | Fixed in |
|---|---|
| iOS and iPadOS | 16.7 |
Every device with Apple iOS and iPadOS needs the update.
Exploitation
CISA added it to its catalog of known exploited vulnerabilities on 5 Oct 2023, within a day of it being made public. CISA lists a flaw only when it has reliable evidence of it being exploited, and gave US federal agencies until 26 Oct 2023 to fix it.[1]
FIRST’s Exploit Prediction Scoring System, which estimates how likely a flaw is to be used in attacks in the next 30 days from what it sees across the internet, puts it at under 1%. That’s in the top 39% of the flaws it scores.[4]
CISA assesses it as not automatable: each attack takes some work.
CISA doesn’t say who was attacked, or how.
Fix
Apple has published a fix or advice.[3] CISA’s required action: “Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.”[1]
- Update Apple iOS and iPadOS now.On iPhone and iPad: Settings, General, Software Update. On a Mac: System Settings, General, Software Update. Install it on every Apple device in the house. Then turn on automatic updates, so the next fix arrives on its own.
- Check you’re on 16.7 or later.Fixed in version 16.7 of iOS and iPadOS. Anything older is what attackers are going after.
- If there’s no update, stop using it.CISA’s advice when a flaw being used in attacks has no fix is to stop using the product until it does.
Timeline
| Date | Event |
|---|---|
| The flaw is made public in the National Vulnerability Database, with a severity score of 7.8.[2] | |
| CISA adds it to its catalog of flaws known to be used in attacks.[1] | |
| CISA’s deadline for US government agencies to fix it.[1] | |
| FIRST puts the odds of it being used in attacks in the next 30 days at under 1%.[4] |
See also
Other Apple iOS and iPadOS flaws
- CVE-2023-41974: use-after-free ·
- CVE-2025-24200: incorrect authorization ·
- CVE-2022-42827: out-of-bounds write ·
- CVE-2021-30983: buffer overflow ·
Other Apple flaws
- CVE-2026-86950, Apple devices: out-of-bounds write ·
- CVE-2026-65400, Apple macOS: improper authentication ·
- CVE-2025-43520, Apple devices: classic buffer overflow ·
- CVE-2025-43510, Apple devices: improper locking ·
- CVE-2025-31277, Apple devices: buffer overflow ·
Similar flaws
- CVE-2026-111357, Ivanti Connect Secure: missing authentication for critical function ·
- CVE-2026-97229, GitLab Community Edition and Enterprise Edition: integer overflow or wraparound ·
- CVE-2026-76418, Cisco Secure Firewall ASA Software and Cisco Secure FTD Software: unchecked return value to NULL pointer dereference ·
- CVE-2026-48356, Adobe Commerce and Magento: unrestricted upload of file with dangerous type ·
- CVE-2026-111497, Google Brotli: unchecked return value ·
Added the same day
- CVE-2023-40044, Progress WS_FTP Server: deserialization of untrusted data ·
- CVE-2023-22515, Atlassian Confluence Data Center and Server: broken access control ·
Every Apple flaw on CISA’s list · Everything added in October 2023
References
- ^ Cybersecurity and Infrastructure Security Agency. “Apple iOS and iPadOS Kernel Privilege Escalation Vulnerability”. Known Exploited Vulnerabilities Catalog, added 5 Oct 2023.
- ^ National Institute of Standards and Technology. “CVE-2023-42824 Detail”. National Vulnerability Database, published 4 Oct 2023.
- ^ Apple. Advisories and fixes: support.apple.com, support.apple.com, support.apple.com, support.apple.com.
- ^ FIRST. “Exploit Prediction Scoring System”. EPSS 0.010, percentile 61.9, 31 Oct 2026.
- CVE Program. “CVE-2023-42824”. The official CVE record.
This article is built from CISA’s catalog (version 2026.10.30), NVD’s record and FIRST’s scores, kept in HARD’s database and checked every morning. The plain English is HARD’s.