CVE-2025-43300
CVE-2025-43300 is a security flaw in Apple iOS, iPadOS, and macOS, the software on Apple’s iPhones, iPads and Macs. Attackers can corrupt memory in Apple iOS, iPadOS, and macOS, which they use to take it over. The US Cybersecurity and Infrastructure Security Agency (CISA) added it to its catalog of flaws known to be used in attacks on 21 Aug 2025.[1]
Apple iOS, iPadOS, and macOS 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 15.8.5, 16.7.12, 18.6.2 and 17.7.10 and others.
Description
CISA calls it an out-of-bounds write in Apple iOS, iPadOS, and macOS. In its words: “Apple iOS, iPadOS, and macOS contain an out-of-bounds write vulnerability in the Image I/O framework.”[1]
The CVE record adds: “An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 15.8.5 and iPadOS 15.8.5, iOS 16.7.12 and iPadOS 16.7.12, iOS 18.6.2 and iPadOS 18.6.2, iPadOS 17.7.10, macOS Sequoia 15.6.1, macOS Sonoma 14.7.8, macOS Ventura 13.7.8. Processing a malicious image file may result in memory corruption. Apple is aware of a report that this issue may have been exploited in an extremely sophisticated attack against specific targeted individuals.”[2]
The underlying weakness is out-of-bounds write (CWE-787), in MITRE’s list of common software weaknesses.
It scores 10.0 out of 10 on the Common Vulnerability Scoring System, which rates it critical, scored by the organisation that published the CVE using CVSS 3.1.[2]
Affected versions
NVD’s record lists these fixed versions: in each line, everything before the version shown is affected.[2]
| Product | Fixed in |
|---|---|
| iOS and iPadOS | 15.8.5 |
| iOS and iPadOS | 16.7.12 |
| iOS and iPadOS | 18.6.2 |
| iPadOS | 17.7.10 |
| macOS | 13.7.8 |
| macOS | 14.7.8 |
| macOS | 15.6.1 |
Every device with Apple iOS, iPadOS, and macOS needs the update.
Exploitation
CISA added it to its catalog of known exploited vulnerabilities on 21 Aug 2025, 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 11 Sep 2025 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 65%. That’s in the top 1% of the flaws it scores.[4]
CISA assesses it as automatable: attackers can run it against many targets at once.
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, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.”[1]
- Update Apple iOS, iPadOS, and macOS 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 15.8.5 or later.Fixed in version 15.8.5, 16.7.12, 18.6.2 and 17.7.10 and others. 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 10.0.[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 65%.[4] |
See also
Other Apple iOS, iPadOS, and macOS flaws
- CVE-2023-41064: imageIO buffer overflow ·
- CVE-2023-28206: iOSurfaceAccelerator out-of-bounds write ·
- CVE-2021-30900: out-of-bounds write ·
- CVE-2022-32917: remote code execution ·
- CVE-2020-9934: input validation ·
- CVE-2022-22620: webkit use-after-free ·
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 ·
Other out-of-bounds write flaws
- CVE-2026-53266, Linux Kernel: out-of-bounds write ·
- CVE-2026-87491, Chrome and other Chromium browsers: out of bounds write ·
- CVE-2026-53362, Linux Kernel: unspecified ·
- CVE-2022-0995, Linux Kernel: out-of-bounds write ·
- CVE-2026-11645, Chrome and other Chromium browsers: out-of-bounds read and write ·
Every Apple flaw on CISA’s list · Everything added in August 2025
References
- ^ Cybersecurity and Infrastructure Security Agency. “Apple iOS, iPadOS, and macOS Out-of-Bounds Write Vulnerability”. Known Exploited Vulnerabilities Catalog, added 21 Aug 2025.
- ^ National Institute of Standards and Technology. “CVE-2025-43300 Detail”. National Vulnerability Database, published 21 Aug 2025.
- ^ Apple. Advisories and fixes: support.apple.com, support.apple.com, support.apple.com, support.apple.com, support.apple.com, and 2 more on NVD’s record.
- ^ FIRST. “Exploit Prediction Scoring System”. EPSS 0.652, percentile 99.3, 31 Oct 2026.
- CVE Program. “CVE-2025-43300”. 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.