Apple macOS up to 14.8.4/15.7.4/26.2 String integer overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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8.0$5k-$25k0.00

Summaryinfo

A vulnerability labeled as very critical has been found in Apple macOS up to 14.8.4/15.7.4/26.2. This vulnerability affects unknown code of the component String Handler. Executing a manipulation can lead to integer overflow. The identification of this vulnerability is CVE-2026-20639. The attack may be launched remotely. There is no exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability has been found in Apple macOS up to 14.8.4/15.7.4/26.2 and classified as very critical. This vulnerability affects an unknown part of the component String Handler. The manipulation with an unknown input leads to a integer overflow vulnerability. The CWE definition for the vulnerability is CWE-190. The product performs a calculation that can produce an integer overflow or wraparound, when the logic assumes that the resulting value will always be larger than the original value. This can introduce other weaknesses when the calculation is used for resource management or execution control. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

An integer overflow was addressed with improved input validation. This issue is fixed in macOS Sequoia 15.7.5, macOS Sonoma 14.8.5, macOS Tahoe 26.3. Processing a maliciously crafted string may lead to heap corruption.

The advisory is available at support.apple.com. This vulnerability was named CVE-2026-20639 since 11/11/2025. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. Successful exploitation requires user interaction by the victim. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $5k-$25k at the moment (estimation calculated on 03/29/2026).

Upgrading to version 14.8.5, 15.7.5 or 26.3 eliminates this vulnerability.

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Productinfo

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Vendor

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Version

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.2
VulDB Meta Temp Score: 8.0

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

ADP CISA Base Score: 7.5
ADP CISA Vector: 🔒

CVSSv2info

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

Exploitinginfo

Class: Integer overflow
CWE: CWE-190 / CWE-189
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: macOS 14.8.5/15.7.5/26.3

Timelineinfo

11/11/2025 CVE reserved
03/25/2026 +134 days Advisory disclosed
03/25/2026 +0 days VulDB entry created
03/29/2026 +4 days VulDB entry last update

Sourcesinfo

Vendor: apple.com

Advisory: support.apple.com
Status: Confirmed

CVE: CVE-2026-20639 (🔒)
GCVE (CVE): GCVE-0-2026-20639
GCVE (VulDB): GCVE-100-352894
scip Labs: https://www.scip.ch/en/?labs.20180712

Entryinfo

Created: 03/25/2026 07:25
Updated: 03/29/2026 16:46
Changes: 03/25/2026 07:25 (56), 03/29/2026 16:46 (12)
Complete: 🔍
Cache ID: 216::103

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