CVE-2026-84543: Apple macOS · Out-of-bounds Read
Affects Apple macOSSource CVE Database V5
Not known to be exploited · CVSS 7.5 High · fixed in 27 : patch Apple macOS soon.
Data as of 30 Oct 2026, 06:59 UTC
Thin evidence
One scorer or none| CISA-ADP | CVSS 3.1 | 7.5 |
|---|
- EPSS
- 0.4% chance of exploitation in 30 days – higher than 37% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 27, 26.7, 15.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:NExploitation evidence
Disclosed: evidence found.
CVE published 14 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: evidence found.
Public exploit code: GitHub proofs of concept
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), GitHub proofs of concept, the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.
What to do
Upgrade Apple macOS to 27, 26.7 or 15.8.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| ApplemacOS | Affected
| Fixed in
|
| ApplemacOS | Affected
| Fixed in
|
| ApplemacOS | Affected
| Fixed in
|
AI-suggested
Apply the official patches by upgrading to macOS versions 15.8, 26.7, or 27 where this vulnerability is fixed. Since fixed versions are available, updating to these releases is the recommended mitigation.
Description
CVE-2026-84543 is a high-severity vulnerability in macOS where connecting to a malicious SMB server can cause unexpected system termination or corrupt kernel memory. The issue is due to an out-of-bounds access that has been addressed with improved bounds checking. This vulnerability affects versions of macOS prior to 15.8, 26.7, and 27, with fixes available in these releases.