Apple Safari/iOS/iPadOS/macOS/visionOS up to 26.3 Web memory corruption

CVSS Meta Temp Score
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CTI Interest Score
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4.2$5k-$25k0.00

Summaryinfo

A vulnerability categorized as critical has been discovered in Apple Safari, iOS, iPadOS, macOS and visionOS up to 26.3. This issue affects some unknown processing of the component Web Handler. Executing a manipulation can lead to memory corruption. This vulnerability is handled as CVE-2026-20664. The attack can be executed remotely. There is not any exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in Apple Safari, iOS, iPadOS, macOS and visionOS up to 26.3. It has been declared as critical. This vulnerability affects an unknown functionality of the component Web Handler. The manipulation with an unknown input leads to a memory corruption vulnerability. The CWE definition for the vulnerability is CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. As an impact it is known to affect availability. CVE summarizes:

The issue was addressed with improved memory handling. This issue is fixed in Safari 26.4, iOS 26.4 and iPadOS 26.4, macOS Tahoe 26.4, visionOS 26.4. Processing maliciously crafted web content may lead to an unexpected process crash.

The advisory is available at support.apple.com. This vulnerability was named CVE-2026-20664 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 05/02/2026).

The vulnerability scanner Nessus provides a plugin with the ID 304078 (Linux Distros Unpatched Vulnerability : CVE-2026-20664), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 26.4 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (304078) and CERT Bund (WID-SEC-2026-0911). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Affected

  • Debian Linux
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • SUSE Linux
  • Oracle Linux
  • RESF Rocky Linux
  • Open Source WebKitGTK

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 4.2

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

ADP CISA Base Score: 4.3
ADP CISA Vector: 🔒

CVSSv2info

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

Exploitinginfo

Class: Memory corruption
CWE: CWE-119
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: 304078
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-20664

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Safari/iOS/iPadOS/macOS/visionOS 26.4

Timelineinfo

11/11/2025 CVE reserved
03/25/2026 +134 days Advisory disclosed
03/25/2026 +0 days VulDB entry created
05/02/2026 +38 days VulDB entry last update

Sourcesinfo

Vendor: apple.com

Advisory: support.apple.com
Status: Confirmed

CVE: CVE-2026-20664 (🔒)
GCVE (CVE): GCVE-0-2026-20664
GCVE (VulDB): GCVE-100-352906
CERT Bund: WID-SEC-2026-0911 - WebKitGTK: Mehrere Schwachstellen

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

Entryinfo

Created: 03/25/2026 07:30
Updated: 05/02/2026 08:13
Changes: 03/25/2026 07:30 (57), 03/29/2026 16:46 (11), 03/30/2026 14:27 (7), 03/31/2026 12:50 (2), 04/22/2026 18:21 (1), 05/02/2026 08:13 (1)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Discussion

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