VulnTideExploited vulnerabilities, by vendor. Data as of .
Not in CISA KEVPublished CVSS 9.8 criticalEPSS 0.5% probability of exploitation in 30 days
Apple

CVE-2026-84539: An out-of-bounds write issue was addressed with improved bounds checking.

Is it exploited?

Not on CISA's list. CISA has not added it to the Known Exploited Vulnerabilities catalog as of . If CISA adds it, this page shows it as known exploited.

How likely is exploitation in the next 30 days?
0.5%

Up from 0.2% on .

EPSS score, percentile 44.8 of all scored records. A probability estimated by FIRST, not a report of exploitation.

How severe?
9.8 Critical

CVSS v3.1 base score, from CISA's enrichment of the record

What should I do?

CISA has set no required action, because the vulnerability is not in KEV.

No patch or vendor advisory is listed in the CVE record. Check Apple's advisories.

Which versions are affected?

Affected

  • before 26.7.2
  • before 27

Versions by product

Source: CISA KEV 2026.11.10, as of ; FIRST EPSS, as of ; CVE List, as of . About the data.

Description

An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in macOS Golden Gate 27, macOS Tahoe 26.7.2. An app may be able to cause unexpected system termination.

Source: CVE List, as of . About the data.

What to do

Advisories and patches

No patch, vendor advisory or mitigation is listed in the CVE record. Check Apple's own security advisories for a fix, and compare your version with the affected versions below.

This summary is based on the CVE record as of . Check the vendor's advisory before you act: affected versions and fixes can change.

Affected products and versions

Versions by product, as listed in the CVE record (1 product)
Apple macOS
StatusVersions
Affectedbefore 26.7.2
Affectedbefore 27

Source: CVE List, as of . About the data.

Weakness

CWE-787

CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record.

Timeline

DateEvent
CVE record published
CVE record last updated

References

2

Known exploited Apple vulnerabilities

  • CVE-2024-27834: Apple Multiple Products Improper Authentication Vulnerability (added )
  • CVE-2026-86950: Apple Multiple Products Out-of-Bounds Write Vulnerability (added )
  • CVE-2026-65400: Apple macOS Improper Authentication Vulnerability (added )
  • CVE-2025-31277: Apple Multiple Products Buffer Overflow Vulnerability (added )
  • CVE-2025-43510: Apple Multiple Products Improper Locking Vulnerability (added )