CVE-2019-8526
CVE-2019-8526 is a security flaw in Apple macOS, the operating system on Macs. Someone who already has a foothold can use Apple macOS 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 17 Apr 2023.[1]
Apple 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 macOS Mojave 10.14.4 of macOS.
Description
CISA calls it an use-after-free in Apple macOS. In its words: “Apple macOS contains a use-after-free vulnerability that could allow for privilege escalation.”[1]
The CVE record adds: “A use after free issue was addressed with improved memory management. This issue is fixed in macOS Mojave 10.14.4. An application may be able to gain elevated privileges.”[2]
The underlying weakness is use after free (CWE-416), in MITRE’s list of common software weaknesses.
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 |
|---|---|
| macOS | macOS Mojave 10.14.4 |
Every device with Apple macOS needs the update.
Exploitation
CISA added it to its catalog of known exploited vulnerabilities on 17 Apr 2023, 1,216 days after it was made public. CISA lists a flaw only when it has reliable evidence of it being exploited, and gave US federal agencies until 8 May 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 47% 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 updates per vendor instructions.”[1]
- Update Apple 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 macOS Mojave 10.14.4 or later.Fixed in version macOS Mojave 10.14.4 of macOS. 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 macOS flaws
- CVE-2026-65400: improper authentication ·
- CVE-2022-22675: out-of-bounds write ·
- CVE-2022-22674: out-of-bounds read ·
- CVE-2021-30713: unspecified ·
- CVE-2021-30657: unspecified ·
Other Apple flaws
- CVE-2026-86950, Apple devices: out-of-bounds write ·
- CVE-2025-43520, Apple devices: classic buffer overflow ·
- CVE-2025-43510, Apple devices: improper locking ·
- CVE-2025-31277, Apple devices: buffer overflow ·
- CVE-2023-43000, Apple devices: use-after-free ·
Other use after free flaws
- CVE-2026-109619, PHP: stale internal request-state ·
- CVE-2026-109618, PHP: memory corruption ·
- CVE-2026-68820, Microsoft Windows Ancillary Function Driver for WinSock: use-after-free ·
- CVE-2010-0249, Microsoft Internet Explorer: use-after-free ·
- CVE-2020-9715, Adobe Acrobat: use-after-free ·
Added the same day
- CVE-2023-2033, Chrome and other Chromium browsers: type confusion ·
Every Apple flaw on CISA’s list · Everything added in April 2023
References
- ^ Cybersecurity and Infrastructure Security Agency. “Apple macOS Use-After-Free Vulnerability”. Known Exploited Vulnerabilities Catalog, added 17 Apr 2023.
- ^ National Institute of Standards and Technology. “CVE-2019-8526 Detail”. National Vulnerability Database, published 18 Dec 2019.
- ^ Apple. Advisories and fixes: support.apple.com, support.apple.com.
- ^ FIRST. “Exploit Prediction Scoring System”. EPSS 0.007, percentile 53.2, 31 Oct 2026.
- CVE Program. “CVE-2019-8526”. 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.