CVE-2023-42917

HIGH

8.8

CVSS Score

Published: November 30, 2023 at 10:18 PM UTC

Updated: June 17, 2026 at 06:24 AM UTC

7 products affected across 4 vendorsmacOSDebian LinuxFedora

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Severity

HIGH8.8

Exploitation

CISA KEV

Exploit prediction

EPSS 9%

SSVC

Active

Actively Exploited

CISA Known Exploited Vulnerabilities (KEV) Catalog

EPSS Score9.3%

EPSS (Exploit Prediction Scoring System) estimates a 9.3% chance this CVE is exploited in the wild within the next 30 days — higher than 95% of all CVEs. It complements CVSS: a high EPSS on a mid-severity CVE can still be urgent.

Apple iOS, iPadOS, macOS, and Safari WebKit contain a memory corruption vulnerability that leads to code execution when processing maliciously crafted web content. This vulnerability could impact HTML parsers that use WebKit, including but not limited to Apple Safari and non-Apple products which rely on WebKit for HTML processing.

Required Action

Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.

Ransomware Use

Unknown

Added to KEV

Dec 4, 2023

Remediation Due

Dec 25, 2023

1036 days overdue

Notes

https://support.apple.com/en-us/HT214031, https://support.apple.com/en-us/HT214032, https://support.apple.com/en-us/HT214033

https://nvd.nist.gov/vuln/detail/CVE-2023-42917

Description

A memory corruption vulnerability was addressed with improved locking. This issue is fixed in iOS 17.1.2 and iPadOS 17.1.2, macOS Sonoma 14.1.2, Safari 17.1.2. Processing web content may lead to arbitrary code execution. Apple is aware of a report that this issue may have been exploited against versions of iOS before iOS 16.7.1.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

iPadOS · Apple

95%

v < 15.8.1v < 17.116.0 ≤ v < 16.7.317.0 ≤ v < 17.1.2

Affected range stops below 15.8.1, so it looks safe — our inference, not a vendor statement

Affected range stops below 16.7.3, so it looks safe — our inference, not a vendor statement

Affected range stops below 17.1, so it looks safe — our inference, not a vendor statement

Affected range stops below 17.1.2, so it looks safe — our inference, not a vendor statement

iPhone OS · Apple

95%

v < 15.8.116.0 ≤ v < 16.7.317.0 ≤ v < 17.1.2

Affected range stops below 15.8.1, so it looks safe — our inference, not a vendor statement

Affected range stops below 16.7.3, so it looks safe — our inference, not a vendor statement

Affected range stops below 17.1.2, so it looks safe — our inference, not a vendor statement

macOS · Apple

95%

v < 14.114.0 ≤ v < 14.1.2

Affected range stops below 14.1, so it looks safe — our inference, not a vendor statement

Affected range stops below 14.1.2, so it looks safe — our inference, not a vendor statement

Safari · Apple

95%

v < 17.1v < 17.1.2

Affected range stops below 17.1, so it looks safe — our inference, not a vendor statement

Affected range stops below 17.1.2, so it looks safe — our inference, not a vendor statement

Debian Linux · Debiandrupal

95%

11.0 12.0

Fedora · Fedora Projectrpm

95%

38 39

WebKitGTK · Webkitgtk

95%

v < 2.42.3

Affected range stops below 2.42.3, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references