Apple Safari/iOS/iPadOS/macOS up to 26.5.1 Web stack-based overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.2$25k-$100k1.23

Summaryinfo

A vulnerability was found in Apple Safari, iOS, iPadOS and macOS up to 26.5.1. It has been declared as critical. The impacted element is an unknown function of the component Web Handler. Such manipulation leads to stack-based overflow. This vulnerability is traded as CVE-2026-43718. The attack may be launched remotely. There is no exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Apple Safari, iOS, iPadOS and macOS up to 26.5.1. Affected by this issue is some unknown processing of the component Web Handler. The manipulation with an unknown input leads to a stack-based overflow vulnerability. Using CWE to declare the problem leads to CWE-121. A stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function). Impacted is confidentiality, integrity, and availability. CVE summarizes:

A stack overflow was addressed with improved input validation. This issue is fixed in Safari 26.5.2, iOS 26.5.2 and iPadOS 26.5.2, macOS Tahoe 26.5.2. Processing maliciously crafted web content may lead to an unexpected Safari crash.

The advisory is shared for download at support.apple.com. This vulnerability is handled as CVE-2026-43718 since 05/02/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $25k-$100k (estimation calculated on 06/30/2026).

Upgrading to version 26.5.2 eliminates this vulnerability.

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Productinfo

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Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.4
VulDB Meta Temp Score: 6.2

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

ADP CISA Base Score: 6.5
ADP CISA Vector: 🔒

CVSSv2info

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

Exploitinginfo

Class: Stack-based overflow
CWE: CWE-121 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
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: Safari/iOS/iPadOS/macOS 26.5.2

Timelineinfo

05/02/2026 CVE reserved
06/29/2026 +58 days VulDB entry created
06/30/2026 +0 days Advisory disclosed
06/30/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: apple.com

Advisory: support.apple.com
Status: Confirmed

CVE: CVE-2026-43718 (🔒)
GCVE (CVE): GCVE-0-2026-43718
GCVE (VulDB): GCVE-100-374744
scip Labs: https://www.scip.ch/en/?labs.20180712

Entryinfo

Created: 06/30/2026 01:10
Changes: 06/30/2026 01:10 (66)
Complete: 🔍
Cache ID: 216::103

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