CVE-2026-43727: 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 Safari crash

Advisory: https://webkitgtk.org/security/WSA-2026-0004.html WebKit Bug: https://bugs.webkit.org/showbug.cgi?id=313691

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, visionOS 26.6, watchOS 26.6. Processing maliciously crafted web content may lead to an unexpected Safari crash.

— MITRE

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. Processing maliciously crafted web content may lead to an unexpected Safari crash.

— NVD

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

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, Maher Azzouzi(Calif)

Affected Software

10 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 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 26.5.2
  2. Upgrade

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

    Fixed in 26.6
  3. Upgrade

    Upgrade Safari to a version that resolves this vulnerability.

    Fixed in 26.5.2
  4. Upgrade

    Upgrade iOS to a version that resolves this vulnerability.

    Fixed in 26.5.2
  5. Upgrade

    Upgrade iPadOS to a version that resolves this vulnerability.

    Fixed in 26.5.2
  6. Upgrade

    Upgrade macOS Tahoe to a version that resolves this vulnerability.

    Fixed in 26.5.2
  7. Upgrade

    Upgrade visionOS to a version that resolves this vulnerability.

    Fixed in 26.6
  8. Upgrade

    Upgrade watchOS to a version that resolves this vulnerability.

    Fixed in 26.6
  9. Configuration

    Use HTTPS when sending information over the network to address the referenced cross-origin/network information handling issue.

    Network communication Use HTTPS when sending information over the network = HTTPS

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
Weakness
Updated
via Apple·12:00 AM
Affected Software
Updated
via Apple·12:00 AM
DescriptionWeaknessAffected Software
Updated
via Apple·12:00 AM
WeaknessAffected Software
CVE Published
via MITRE·07:43 PM
Data Sourced
via MITRE·07:43 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
Updated
via Apple·12:00 AM
DescriptionAffected Software
Updated
via Apple·12:00 AM
Affected Software

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

Free Weekly Intel

Don't miss critical vulnerabilities

Join thousands of security professionals who receive our weekly digest of trending CVEs, zero-days, and exploited vulnerabilities.

No spam. Unsubscribe anytime.

Frequently Asked Questions

1

What is the severity of CVE-2026-43727?

CVE-2026-43727 has a medium severity rating of 6.5 according to the CVSS 3.1 scoring system.

2

How do I fix CVE-2026-43727?

To fix CVE-2026-43727, update to Safari 26.5.2, iOS 26.5.2, iPadOS 26.5.2, or macOS Tahoe 26.5.2.

3

What could happen if I don't address CVE-2026-43727?

Failure to address CVE-2026-43727 could result in Safari crashing due to processing maliciously crafted web content.

4

What type of issue is CVE-2026-43727?

CVE-2026-43727 is a use-after-free vulnerability that also involves a race condition.

5

Which platforms are affected by CVE-2026-43727?

CVE-2026-43727 affects Apple iPadOS, Apple Safari, Apple iOS, Apple macOS Tahoe, and Apple iPhone OS.

Company

Resources

Contact

SecAlerts Pty Ltd.
132 Wickham Terrace
Fortitude Valley,
QLD 4006, Australia
info@secalerts.co
By using SecAlerts services, you agree to our services end-user license agreement. This website is safeguarded by reCAPTCHA and governed by the Google Privacy Policy and Terms of Service. All names, logos, and brands of products are owned by their respective owners, and any usage of these names, logos, and brands for identification purposes only does not imply endorsement. If you possess any content that requires removal, please get in touch with us.
© 2026 SecAlerts Pty Ltd.
ABN: 70 645 966 203, ACN: 645 966 203