CVE-2023-42917: Apple Multiple Products WebKit Memory Corruption Vulnerability

Q: How do I fix CVE-2023-42917?

safari: upgrade to 17.1.2; ipados: upgrade to 15.8.1, 16.7.3, 17.1.2; iphone os: upgrade to 15.8.1, 16.7.3, 17.1.2. Exact commands for each OS are on this page.

Q: Is CVE-2023-42917 being exploited?

Yes. CVE-2023-42917 is on the CISA Known Exploited Vulnerabilities list, so treat it as patch-now.

Q: What does CVE-2023-42917 affect?

CVE-2023-42917 affects safari, ipados, iphone os. Severity is high (CVSS 8.8). 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

Q: How urgent is CVE-2023-42917?

Priority 85/100. High severity; EPSS top 5%: very likely to be exploited; Exploited in the wild (CISA KEV); On your watchlist

Patch now

HIGH 8.8EXPLOITEDWATCHLISTUPGRADEUPGRADEUPGRADE

CVE-2023-42917 is a high-severity flaw (CVSS 8.8) affecting safari, ipados, iphone os, reported as exploited in the wild. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

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.

Why this priority

High severity
EPSS top 5%: very likely to be exploited
Exploited in the wild (CISA KEV)
On your watchlist

A fixed release or distro patch exists.

Risk facts

CVSS score	8.8 (High)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	Required
EPSS exploit chance	9.3% (top 5%)
CISA exploited list	Yes, fix due 2023-12-25
Weakness	CWE-787
Published	2023-11-30
Last modified	2026-06-17

Publisher (CNA): Apple Inc. · Vendor: apple · debian · fedoraproject

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2023-11-30 23:15 UTCPublished CVE record published
2023-12-04Exploited Added to the CISA Known Exploited Vulnerabilities list
2023-12-25Deadline CISA due date for US federal agencies to patch
2026-06-17 06:24 UTCUpdated Record last modified

apple safari UPGRADE

Affected: < 17.1.2

Fixed in: 17.1.2

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy safari || rpm -q safari || safari --version

2. UPGRADE to 17.1.2 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade safari

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade safari

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

apple ipados UPGRADE

Affected: < 15.8.1 · >= 16.0 and < 16.7.3 · >= 17.0 and < 17.1.2

Fixed in: 15.8.1, 16.7.3, 17.1.2

Safe to downgrade to: a release before 16.0

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

apple iphone os UPGRADE

Affected: < 15.8.1 · >= 16.0 and < 16.7.3 · >= 17.0 and < 17.1.2

Fixed in: 15.8.1, 16.7.3, 17.1.2

Safe to downgrade to: a release before 16.0

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

apple macos UPGRADE

Affected: >= 14.0 and < 14.1.2

Fixed in: 14.1.2

Safe to downgrade to: a release before 14.0

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

debian debian linux MITIGATE

Affected: 11.0 · 12.0

Fixed in: no fixed release known

Safe to downgrade to: a release before 11.0

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

fedoraproject fedora MITIGATE

Affected: 38 · 39

Fixed in: no fixed release known

Safe to downgrade to: a release before 38

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

Exact fixes by distribution

A distro patch exists: prefer upgrading over downgrading.

Fedora ELN · libmamba · FIXED · 2.10.0-1.eln159 · FEDORA-2026-cc57be9e65 · source

sudo dnf upgrade --advisory=FEDORA-2026-cc57be9e65

Fedora 46 · rubygem-selenium-webdriver · FIXED · 4.34.0-5.fc46 · FEDORA-2026-111c6e6363 · source

sudo dnf upgrade --advisory=FEDORA-2026-111c6e6363

Ubuntu 22.04 · webkit2gtk · FIXED · 2.42.3-0ubuntu0.22.04.1

sudo apt update && sudo apt install --only-upgrade webkit2gtk dpkg --compare-versions "$(dpkg-query -W -f='${Version}' webkit2gtk)" ge "2.42.3-0ubuntu0.22.04.1" && echo PATCHED || echo STILL-VULNERABLE

Ubuntu 24.04 · webkit2gtk · FIXED · 2.42.3-1

sudo apt update && sudo apt install --only-upgrade webkit2gtk dpkg --compare-versions "$(dpkg-query -W -f='${Version}' webkit2gtk)" ge "2.42.3-1" && echo PATCHED || echo STILL-VULNERABLE

Debian 12 · webkit2gtk · FIXED · 2.42.3-1~deb12u1

sudo apt update && sudo apt install --only-upgrade webkit2gtk dpkg --compare-versions "$(dpkg-query -W -f='${Version}' webkit2gtk)" ge "2.42.3-1~deb12u1" && echo PATCHED || echo STILL-VULNERABLE

Debian 13 · webkit2gtk · FIXED · 2.42.3-1

sudo apt update && sudo apt install --only-upgrade webkit2gtk dpkg --compare-versions "$(dpkg-query -W -f='${Version}' webkit2gtk)" ge "2.42.3-1" && echo PATCHED || echo STILL-VULNERABLE

Debian 12 · wpewebkit · NO FIX YET

Debian 13 · wpewebkit · FIXED · 2.42.3-1

sudo apt update && sudo apt install --only-upgrade wpewebkit dpkg --compare-versions "$(dpkg-query -W -f='${Version}' wpewebkit)" ge "2.42.3-1" && echo PATCHED || echo STILL-VULNERABLE

RHEL 7 Extended Lifecycle Support · webkitgtk4 · FIXED · webkitgtk4-2.48.3-2.el7_9

sudo dnf upgrade --advisory=RHSA-2025:10364 rpm -q webkitgtk4

RHEL 8 · webkit2gtk3 · FIXED · webkit2gtk3-2.40.5-1.el8_9.1

sudo dnf upgrade --advisory=RHSA-2023:7716 rpm -q webkit2gtk3

RHEL 8.2 Advanced Update Support · webkit2gtk3 · FIXED · webkit2gtk3-2.46.3-1.el8_2

sudo dnf upgrade --advisory=RHSA-2024:9680 rpm -q webkit2gtk3

RHEL 8.4 Advanced Mission Critical Update Support · webkit2gtk3 · FIXED · webkit2gtk3-2.46.3-1.el8_4

sudo dnf upgrade --advisory=RHSA-2024:9679 rpm -q webkit2gtk3

RHEL 8.4 Telecommunications Update Service · webkit2gtk3 · FIXED · webkit2gtk3-2.46.3-1.el8_4

sudo dnf upgrade --advisory=RHSA-2024:9679 rpm -q webkit2gtk3

Amazon Linux 2 · see advisory · FIXED · ALAS2-2024-2427 · source

sudo yum update --advisory=ALAS2-2024-2427

Verify at the official source NVD · CVE Program · CISA KEV catalog · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2023-42917?

safari: upgrade to 17.1.2; ipados: upgrade to 15.8.1, 16.7.3, 17.1.2; iphone os: upgrade to 15.8.1, 16.7.3, 17.1.2. Exact commands for each OS are on this page.

Is CVE-2023-42917 being exploited?

Yes. CVE-2023-42917 is on the CISA Known Exploited Vulnerabilities list, so treat it as patch-now.

What does CVE-2023-42917 affect?

CVE-2023-42917 affects safari, ipados, iphone os. Severity is high (CVSS 8.8). 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

How urgent is CVE-2023-42917?

Priority 85/100. High severity; EPSS top 5%: very likely to be exploited; Exploited in the wild (CISA KEV); On your watchlist

Software pages

Debian vulnerabilities · iOS vulnerabilities · macOS vulnerabilities · Safari vulnerabilities · WebKit vulnerabilities · Apple Safari and WebKit vulnerabilities

Related CVEs

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CVE-2026-43715 HIGH 8.8 UPGRADE UPGRADE A use-after-free issue was addressed with improved memory management
CVE-2025-43342 CRITICAL 9.8 UPGRADE UPGRADE A correctness issue was addressed with improved checks
CVE-2025-43343 CRITICAL 9.8 UPGRADE UPGRADE The issue was addressed with improved memory handling
CVE-2025-43376 HIGH 7.5 UPGRADE UPGRADE A logic issue was addressed with improved state management

References

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