VDB-383699 · CVE-2026-64691 · GCVE-0-2026-64691

Apple macOS up to 26.5 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.
7.8	$0-$5k	3.47

Summaryinfo

A vulnerability, which was classified as very critical, has been found in Apple macOS up to 26.5. This affects an unknown function. The manipulation leads to buffer overflow. This vulnerability is traded as CVE-2026-64691. An attack has to be approached locally. There is no exploit available.

Detailsinfo

A vulnerability, which was classified as very critical, has been found in Apple macOS up to 26.5. This issue affects an unknown functionality. The manipulation with an unknown input leads to a buffer overflow vulnerability. Using CWE to declare the problem leads to 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. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

A buffer overflow was addressed with improved size validation. This issue is fixed in macOS Tahoe 26.6. An app may be able to cause unexpected system termination.

It is possible to read the advisory at support.apple.com. The identification of this vulnerability is CVE-2026-64691 since 07/20/2026. The exploitation is known to be easy. Attacking locally is a requirement. It demands that the victim is doing some kind of user interaction. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 07/28/2026).

Upgrading to version 26.6 eliminates this vulnerability.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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: 8.2
VulDB Meta Temp Score: 7.8

VulDB Base Score: 8.2
VulDB Temp Score: 7.8
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: Partially

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 26.6

Timelineinfo

07/20/2026 CVE reserved
07/27/2026 +7 days VulDB entry created
07/28/2026 +0 days Advisory disclosed
07/28/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: apple.com

Advisory: support.apple.com
Status: Confirmed

CVE: CVE-2026-64691 (🔒)
GCVE (CVE): GCVE-0-2026-64691
GCVE (VulDB): GCVE-100-383699
scip Labs: https://www.scip.ch/en/?labs.20180712

Entryinfo

Created: 07/28/2026 00:59
Changes: 07/28/2026 00:59 (55)
Complete: 🔍
Cache ID: 216::103