CVE-2026-43734: Double Free

Published Jun 29, 2026
·
Updated

A use-after-free issue was addressed with improved memory management.

Impact: maliciously crafted web content may cause unexpected process crash

Advisory: https://webkitgtk.org/security/WSA-2026-0004.html WebKit Bug: https://bugs.webkit.org/showbug.cgi?id=313693

Other sources

A use-after-free issue was addressed with improved memory management. This issue is fixed in Safari 26.5.2, iOS 26.5.2 and iPadOS 26.5.2, macOS Tahoe 26.5.2, tvOS 26.6, visionOS 26.6, watchOS 26.6. Processing maliciously crafted web content may lead to an unexpected process crash.

— MITRE

Accounts Framework. This issue was addressed with improved data protection.

— Apple

App Store. This issue was addressed with improved checks.

— Apple

Apple Neural Engine. A use after free issue was addressed with improved memory management.

— Apple

Audio. An out-of-bounds write issue was addressed with improved bounds checking.

— Apple

Credit

Hyunwoo Kim@@v4bel, Feng Xue(ThreatBook), XGPT(ThreatBook), Vladislav Shevchenko (Positive Technologies)(Baidu Security), Ye Zhang@@VAR10CK(Baidu Security), Billy Jheng Bing Jhong(STAR Labs SG Pte), Pan Zhenpeng@@Peterpan0927(STAR Labs SG Pte), Tristan Madani@@TristanInSec(Talence Security), dr3dd, Vitaly Simonovich, Christian Meurer Xavier, Merrick Hare, Drinor Selmanaj (Sentry), Khai Tran, John Lussier, Rhyru9, Kwak Kiyong, Song Nuri, Jonathan Alush-Aben, Josef Korbel (Citadelo)(Talence Security), Gia Bui@@yabeow(Calif), Narendra Singh@@_3P1C, CVE-2026-43709, Tommy DeVoss@@thedawgyg(Braze Security Team), Юлия Мерцалова, Nan Wang@@eternalsakura13, Milad Nasr, Nicholas Carlini with Claude, Anthropic, Gurpreet Shergill, Luke Francis, Soyeon Park(DEVCORE Research Team), Amy Burnett(DEVCORE Research Team), Khai Tran(DEVCORE Research Team), sherkito(DEVCORE Research Team), Kota Toda(DEVCORE Research Team), HexRabbit@@h3xr4bb1t(DEVCORE Research Team), NiNi@@terrynini38514(DEVCORE Research Team), Using GLM(Z), Brian Carpenter, Utkarsh Pal, Ignacio Sanmillan@@ulexec, Kwak Kiyong(Talence Security), Song Nuri(Talence Security), Tuan(Calif), Duc(Calif), OpenAI Codex Security - Amy Burnett, Evan Lambert, Mateusz Krzywicki (iVerify.io)(Braze Security Team), dr3dd(Braze Security Team), Nathaniel Oh@@calysteon, Arni Hardarson, Jody Ritonga, Behzad Najjarpour Jabbari@@_G4ru_, Aaron Grattafiori - NVIDIA AI Red Team, Josef Korbel, Idan Masas, CVE-2026-28979, Lyutoon, Dun, Seonung Park, ALTV!ST (altvi.st/), David Strnadel, Franco Belman at Blackwing Intelligence, Anton Pakhunov, Rodolphe BRUNETTI@@eisw0lf(Lupus Nova), Daniel Febrero, Daniel Williams, Anonymous(TrendAI Zero Day Initiative), Mathis Mansière, an anonymous researcher, Rahul Raj, James Duffy@@0x4A616D657344, 이재영, Rajdip Dey Sarkar, Arni Hardarson (Neonix Security), CVE-2026-3784, CVE-2026-3783, HvxyZLF, Huỳnh Tấn Ngàn, Ilya Andr (andrd3v)(Positive Technologies), Stanislav Jelezoglo, Redon Gashi, Michael DePlante@@izobashi(TrendAI Zero Day Initiative), Peter Malone, 진규정 (Gyujeong Jin, @@G1uN4sh, PETOWORKS의 Bugeun Choi@@Bugeun, Geonha Lee@@leegn4a, f0r(MurphySec), Mahmoud Abdelmoniem, Wang Yu, Hiroki Imai (LAC Co., Ltd.), DARKNAVY@@DarkNavyOrg, Fábio Luís@@scanpt, Nicolas Rabrenovic, Pasquale Scola(STAR Labs SG Pte), Gor Aleksanyan, impost0r (ret2plt)(Appknox), Ruslan Dautov(Appknox), Aleksandr Tarasikov(Appknox), jay(Appknox), Dhiyanesh Selvaraj@@redroot97(Appknox), Vinay Kumar Rasala (Xplo8E)(Appknox), Lyutoon(STAR Labs SG Pte), DongJun Kim (smlijun) with UIUC(STAR Labs SG Pte), Hwiwon Lee (hwiwonl) with UIUC(STAR Labs SG Pte), Jongseong Kim (nevul37) with UIUC(STAR Labs SG Pte), Younggi Park (grill66) with UIUC(STAR Labs SG Pte), Peter Malone(STAR Labs SG Pte), an anonymous researcher(STAR Labs SG Pte), Hari Shanmugam (The Hxr1)(STAR Labs SG Pte), Marco Grassi, Daniele Castronovo, Michal Kosiorek, Josh Maine(Calif), Ruslan Dautov(Baidu Security), 재영 정(Baidu Security), (Rao Ali Nawaz)@@rootxran(Baidu Security), Chanwit Muenprakoddee (ChemIndy)(Baidu Security), an anonymous researcher(Baidu Security), Franco Belman at Blackwing Intelligence(Calif), Christian Figueroa(Calif), Johnny Franks@@zeroxjf(Calif), Ashmit Sharma & Atul RV(Calif), Peter Malone(Calif), Muhamad Syaiful(Calif), Muneeb Amin Bhat(Calif), Dhiyanesh Selvaraj@@redroot97(Calif), Ali Marzouq(Calif), Bountyy Oy - Mihalis Haatainen(Calif), Huy Nguyen@@34306(Calif), Eddy Tsalolikhin, beist(ASU SEFCOM), Adam Doupé(ASU SEFCOM), Dun(STAR Labs SG Pte), Johnny Franks@@zeroxjf, Somair Ansar(Calif), Asjid Kalam@@odinshell, Abhijeet Singh (linkedin.com/in/abhiunix/), Omar Cerrito, impost0r (ret2plt), Ryan Hileman via Xint Code (xint.io), Jian Zhou, Ye Zhang, N.M.Praveen Nawarathne@@zblockrat, Lukas Gerlach, Daisuke Hatakeyama Research)@@SYZD, Richard Zana(Nosebeard Labs), Andreas Jaegersberger & Ro Achterberg(Nosebeard Labs), 彦辰, stratan@@5tratan, stratan@@5tratan(Almamater Technologies), Kagami Rosylight(Mozilla), 杉山 壮太(Z), lattice(Z), Behzad Najjarpour Jabbari@@_G4ru_(Z), Junyeong Lee(Z), Mooth.ai(Z), OGINOME Tomohito(Z), Song nuri(Talence Security), OGINOME Tomohito, Shaheen Fazim, Rosyna Keller(Totally Not Malicious Software), YingQi Shi@@Mas0nShi(DBAppSecurity's WeBin lab), Ashish Kunwar, hxr1, CVE-2026-4424, wh0am1i, Francisco Knabe, Josef Korbel (Citadelo), Tristan Madani, Soyeon Park, Amy Burnett, Heiko Kiesel(SEEMOO), TU Darmstadt, Manuel Fernandez (Stackhopper Security), Tien-Chih Lin(CyCraft Technology), Maher Azzouzi(Calif)

Affected Software

11 affected componentsFixes available
Apple iOS<26.5.2
26.5.2
Apple iPadOS<26.5.2
26.5.2
Apple macOS Tahoe<26.5.2
26.5.2
Apple Safari<26.5.2
Apple iPadOS<26.5.2
Apple iPhone OS<26.5.2
Apple macOS>=26.0<26.5.2
Apple WatchOS<26.6
26.6
Apple visionOS<26.6
26.6
Apple tvOS<26.6
26.6
Apple Safari<26.5.2
26.5.2

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 26.6
  2. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 26.5.2

Event History

Jun 29, 2026
Data Sourced
via Apple·12:00 AM
DescriptionWeaknessAffected Software
Updated
via Apple·12:00 AM
DescriptionWeakness
Updated
via Apple·12:00 AM
DescriptionWeaknessAffected Software
Updated
via Apple·12:00 AM
Affected Software
CVE Published
via MITRE·07:42 PM
Data Sourced
via MITRE·07:42 PM
DescriptionWeakness
Data Sourced
via NVD·08:17 PM
DescriptionSeverityWeaknessAffected Software
Jul 14, 2026
Data Sourced
via Red Hat·07:10 PM
DescriptionSeverityAffected Software
Jul 27, 2026
Updated
via Apple·12:00 AM
DescriptionWeaknessAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

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Frequently Asked Questions

1

What is the severity of CVE-2026-43734?

The severity of CVE-2026-43734 is medium with a CVSS score of 6.5.

2

How do I fix CVE-2026-43734?

To fix CVE-2026-43734, users should update to Safari 26.5.2, iOS 26.5.2, iPadOS 26.5.2, or macOS Tahoe 26.5.2.

3

What are the consequences of CVE-2026-43734?

CVE-2026-43734 may lead to an unexpected process crash when processing maliciously crafted web content.

4

What types of issues are associated with CVE-2026-43734?

CVE-2026-43734 is associated with use-after-free, race conditions, and memory management vulnerabilities.

5

Which software is affected by CVE-2026-43734?

CVE-2026-43734 affects Apple Safari, iOS, iPadOS, macOS Tahoe, and iPhone OS.

Company

Resources

Contact

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