Read the docs
TI-2026-76676 Aliases CVE-2026-86871GHSA-g6m6-98mf-rjcv

Integer underflow in Apple macOS allows unexpected system termination

Priority LOW 27CWE-190Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
High
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA. Impact type from CWE-190 and the CVSS impact.

Summary

Apple macOS versions before 15.8, before 26.7 and before 27 are affected. Improper input validation (CWE-20) lets an integer underflow occur. An attacker who controls a network file server can cause the system to terminate unexpectedly.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Description from the CNA

An integer underflow was addressed with improved input validation. This issue is fixed in macOS Golden Gate 27, macOS Sequoia 15.8, macOS Tahoe 26.7. An attacker with control of a network file server may be able to cause unexpected system termination.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00489 42nd percentileScored 2026-11-07
Fix Fixed macOS (Apple): 15.8, 26.7, 27

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
ApplemacOSbefore 15.8; before 26.7; before 2715.8, 26.7, 27Patch availableCNA
  • macOS VendorApple Affected before 15.8; before 26.7; before 27 Fixed in 15.8, 26.7, 27 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:o:apple:macos:*:*:*:*:*:*:*:*before 15.8; 26.0 to before 26.7VulnerableApple
  • cpe:2.3:o:apple:macos:*:*:*:*:*:*:*:* Versions before 15.8; 26.0 to before 26.7 Vulnerable ·Apple

Remediation

Update to macOS Sequoia 15.8, macOS Tahoe 26.7 or macOS Golden Gate 27, which fix the flaw.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

  • Fix · CNA macOS (Apple) Fixed in 15.8, 26.7, 27

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    Apple macOS 15.8, 26.7, 27

    15 records Highest priority Priority MEDIUM 3 MEDIUM, 12 LOW

    Other records, highest priority first

    • TI-2026-76675 Authentication issue in Apple macOS lets attackers impersonate usersPriority MEDIUM 48
    • TI-2026-76672 Improper checks in Apple macOS lead to unexpected software executionPriority MEDIUM 41
    • TI-2026-76685 Stack overflow in Apple iOS, macOS and visionOS allows code executionPriority MEDIUM 40
    Show all 15 records →

Timeline

  1. 2026-10-20 Threatist record created from CVE-2026-86871
  2. 2026-10-20 CVSS score added · CISA ADP
  3. 2026-10-20 Weakness changed · CISA ADP
  4. 2026-10-20 CISA SSVC decision points changed
  5. 2026-10-20 Alias added: GHSA-g6m6-98mf-rjcv

References

Advisory 3

  • TI-2026-46583 Improper authentication in Apple macOS KEVCVSS 3.1CRITICAL 9.8
  • TI-2025-28008 Out-of-bounds write in Apple iOS and iPadOS KEVCVSS 3.1CRITICAL 10.0
  • TI-2025-22441 Apple iOS and iPadOS: An attacker with arbitrary read and write capability may be able to… KEVCVSS 3.1CRITICAL 9.8
  • TI-2025-22440 Memory corruption in Apple iOS and iPadOS KEVCVSS 3.1CRITICAL 9.8
  • TI-2025-17951 Out-of-bounds write in Apple Safari KEVCVSS 3.1CRITICAL 10.0
  • TI-2025-17847 Use after free in Apple iOS and iPadOS KEVCVSS 3.1CRITICAL 10.0
See all 3490 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences