VDB-403914 · CVE-2026-84520 · GCVE-0-2026-84520

Apple macOS up to 26 buffer overflow

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
8.4	$0-$5k	0.33-

Summaryinfo

A vulnerability classified as very critical was found in Apple macOS up to 26. Impacted is an unknown function. The manipulation results in buffer overflow. This vulnerability is cataloged as CVE-2026-84520. The attack must be initiated from a local position. There is no exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability, which was classified as very critical, was found in Apple macOS up to 26. Affected is an unknown function. The manipulation with an unknown input leads to a buffer overflow vulnerability. CWE is classifying the issue as CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

A buffer overflow was addressed with improved size validation. This issue is fixed in macOS Golden Gate 27. A local attacker may be able to cause unexpected system termination or corrupt kernel memory.

The advisory is available at support.apple.com. This vulnerability is traded as CVE-2026-84520 since 09/01/2026. The exploitability is told to be easy. Local access is required to approach this attack. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 09/15/2026).

Upgrading to version 27 eliminates this vulnerability.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

Operating System

Vendor

Apple

Name

macOS

Version

License

commercial

Website

Vendor: https://www.apple.com/

CPE 2.3info

🔒

CPE 2.2info

🔒

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.8
VulDB Meta Temp Score: 8.4

VulDB Base Score: 8.8
VulDB Temp Score: 8.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Buffer overflow
CWE: CWE-120 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: No

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: macOS 27

Timelineinfo

09/01/2026 CVE reserved
09/14/2026 +13 days VulDB entry created
09/15/2026 +0 days Advisory disclosed
09/15/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: apple.com

Advisory: support.apple.com
Status: Confirmed

CVE: CVE-2026-84520 (🔒)
GCVE (CVE): GCVE-0-2026-84520
GCVE (VulDB): GCVE-100-403914
scip Labs: https://www.scip.ch/en/?labs.20180712

Entryinfo

Created: 09/15/2026 01:11
Changes: 09/15/2026 01:11 (55)
Complete: 🔍
Cache ID: 216::103