Apple iOS/iPadOS/macOS up to 26.5.1 Web denial of service

CVSS Meta Temp Score
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CTI Interest Score
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5.3$5k-$25k0.00-

Summaryinfo

A vulnerability marked as problematic has been reported in Apple iOS, iPadOS and macOS up to 26.5.1. The affected element is an unknown function of the component Web Handler. Performing a manipulation results in denial of service. This vulnerability is identified as CVE-2026-43703. The attack can be initiated remotely. There is not any exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Apple iOS, iPadOS and macOS up to 26.5.1. It has been classified as problematic. This affects an unknown code of the component Web Handler. The manipulation with an unknown input leads to a denial of service vulnerability. CWE is classifying the issue as CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. This is going to have an impact on availability. The summary by CVE is:

The issue was addressed with improved memory handling. This issue is fixed in iOS 26.5.2 and iPadOS 26.5.2, macOS Tahoe 26.5.2. Processing maliciously crafted web content may lead to an unexpected process crash.

The advisory is shared at support.apple.com. This vulnerability is uniquely identified as CVE-2026-43703 since 05/02/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 06/30/2026). MITRE ATT&CK project uses the attack technique T1499 for this issue.

The vulnerability scanner Nessus provides a plugin with the ID 323673 (macOS 26.x < 26.5.2 Multiple Vulnerabilities (127595)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 26.5.2 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (323673). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

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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: 5.4
VulDB Meta Temp Score: 5.3

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
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: Denial of service
CWE: CWE-404
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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Nessus ID: 323673
Nessus Name: macOS 26.x < 26.5.2 Multiple Vulnerabilities (127595)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: 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-2026-43703 (🔒)
GCVE (CVE): GCVE-0-2026-43703
GCVE (VulDB): GCVE-100-374721
scip Labs: https://www.scip.ch/en/?labs.20180712

Entryinfo

Created: 06/30/2026 01:02
Updated: 06/30/2026 09:37
Changes: 06/30/2026 01:02 (66), 06/30/2026 09:37 (2)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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