Apple Safari/macOS/watchOS/visionOS/iOS/iPadOS/tvOS up to 26.2 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 has been found in Apple Safari, macOS, watchOS, visionOS, iOS, iPadOS and tvOS up to 26.2 and classified as critical. Impacted is an unknown function of the component Web Handler. This manipulation causes memory corruption. This vulnerability is handled as CVE-2026-20635. The attack can be initiated remotely. There is not any exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability classified as critical was found in Apple Safari, macOS, watchOS, visionOS, iOS, iPadOS and tvOS up to 26.2. Affected by this vulnerability is an unknown part 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. The summary by CVE is:

The issue was addressed with improved memory handling. This issue is fixed in watchOS 26.3, tvOS 26.3, macOS Tahoe 26.3, iOS 18.7.5 and iPadOS 18.7.5, visionOS 26.3, iOS 26.3 and iPadOS 26.3, Safari 26.3. Processing maliciously crafted web content may lead to an unexpected process crash.

It is possible to read the advisory at support.apple.com. This vulnerability is known as CVE-2026-20635 since 11/11/2025. 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. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 03/22/2026).

The vulnerability scanner Nessus provides a plugin with the ID 303253 (Debian dsa-6172 : gir1.2-javascriptcoregtk-4.0 - security update), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 26.3 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (303253). Statistical analysis made it clear that VulDB provides the best quality for 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: 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

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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: 303253
Nessus Name: Debian dsa-6172 : gir1.2-javascriptcoregtk-4.0 - security update

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Safari/macOS/watchOS/visionOS/iOS/iPadOS/tvOS 26.3

Timelineinfo

11/11/2025 CVE reserved
02/12/2026 +93 days Advisory disclosed
02/12/2026 +0 days VulDB entry created
03/22/2026 +38 days VulDB entry last update

Sourcesinfo

Vendor: apple.com

Advisory: support.apple.com
Status: Confirmed

CVE: CVE-2026-20635 (🔒)
GCVE (CVE): GCVE-0-2026-20635
GCVE (VulDB): GCVE-100-345691
scip Labs: https://www.scip.ch/en/?labs.20180712

Entryinfo

Created: 02/12/2026 06:37
Updated: 03/22/2026 18:37
Changes: 02/12/2026 06:37 (57), 02/13/2026 05:06 (10), 03/22/2026 18:37 (2)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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