Apple iOS/iPadOS/macOS/tvOS/visionOS/watchOS up to 18.7.8/26.4 Web denial of service

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.4$5k-$25k0.00

Summaryinfo

A vulnerability marked as problematic has been reported in Apple iOS, iPadOS, macOS, tvOS, visionOS and watchOS up to 18.7.8/26.4. This affects an unknown function of the component Web Handler. This manipulation causes denial of service. This vulnerability is handled as CVE-2026-28955. The attack can be initiated remotely. There is not any exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability has been found in Apple iOS, iPadOS, macOS, tvOS, visionOS and watchOS up to 18.7.8/26.4 and classified as problematic. Affected by this vulnerability is an unknown code of the component Web Handler. The manipulation with an unknown input leads to a denial of service vulnerability. The CWE definition for the vulnerability is CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. As an impact it is known to affect availability. The summary by CVE is:

The issue was addressed with improved memory handling. This issue is fixed in Safari 26.5, iOS 18.7.9 and iPadOS 18.7.9, iOS 26.5 and iPadOS 26.5, macOS Tahoe 26.5, tvOS 26.5, visionOS 26.5, watchOS 26.5. Processing maliciously crafted web content may lead to an unexpected process crash.

The advisory is shared at support.apple.com. This vulnerability is known as CVE-2026-28955 since 03/03/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. 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 07/02/2026). MITRE ATT&CK project uses the attack technique T1499 for this issue.

The vulnerability scanner Nessus provides a plugin with the ID 318341 (Linux Distros Unpatched Vulnerability : CVE-2026-28955), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 18.7.9 or 26.5 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (318341) and CERT Bund (WID-SEC-2026-1543). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

  • Apple Safari

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.6
VulDB Meta Temp Score: 6.4

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

ADP CISA Base Score: 8.8
ADP CISA Vector: 🔒

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
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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: 318341
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-28955

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: iOS/iPadOS/macOS/tvOS/visionOS/watchOS 18.7.9/26.5

Timelineinfo

03/03/2026 CVE reserved
05/12/2026 +69 days Advisory disclosed
05/12/2026 +0 days VulDB entry created
07/02/2026 +51 days VulDB entry last update

Sourcesinfo

Vendor: apple.com

Advisory: support.apple.com
Status: Confirmed

CVE: CVE-2026-28955 (🔒)
GCVE (CVE): GCVE-0-2026-28955
GCVE (VulDB): GCVE-100-362821
CERT Bund: WID-SEC-2026-1543 - Apple Safari: Mehrere Schwachstellen

scip Labs: https://www.scip.ch/en/?labs.20180712

Entryinfo

Created: 05/12/2026 04:12
Updated: 07/02/2026 22:59
Changes: 05/12/2026 04:12 (57), 05/16/2026 13:22 (7), 05/23/2026 04:18 (12), 06/03/2026 14:48 (2), 07/02/2026 22:59 (6)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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