CVE-2026-28955: Apple Safari Web Inspector WebCore Style Resolver Use-After-Free Remote Code Execution Vulnerability

Published May 11, 2026
·
Updated

Accelerate. An out-of-bounds read was addressed with improved bounds checking.

Other sources

Accounts. A permissions issue was addressed with additional restrictions.

— Apple

Accounts. An authorization issue was addressed with improved state management.

— Apple

AirDrop. A reachable assertion was addressed with improved input validation.

— Apple

APFS. A buffer overflow was addressed with improved bounds checking.

— Apple

App Intents. A logic issue was addressed with improved restrictions.

— Apple

Credit

Cantina, Luke Francis, Vaagn Vardanian, kwak kiyong / kakaogames, Vitaly Simonovich, Adel Bouachraoui, greenbynox, Do Young Park, Artem Dinaburg(Trail of Bits via Anthropic CVD), Yuhao Hu, Yuanming Lai, Chenggang Wu, Zhe Wang, Idan Masas(TrendAI Zero Day Initiative), DARKNAVY@@DarkNavyOrg(TrendAI Zero Day Initiative), Anonymous(TrendAI Zero Day Initiative), Daniel Rhea, Luka Rački, wac(TrendAI Zero Day Initiative), Kookhwan Lee(TrendAI Zero Day Initiative), Mateusz Krzywicki (iVerify.io), Maher Azzouzi, Tristan Madani@@TristanInSec(Talence Security), Nathaniel Oh@@calysteon, Aisle offensive security research team (Joshua Rogers(Calif), Luigino Camastra(Calif), Igor Morgenstern(Calif), (Calif), Guido Vranken)(Calif), Maher Azzouzi(Calif), Ngan Nguyen(Calif), an anonymous researcher, dr3dd, Gia Bui@@yabeow(Calif), w0wbox, Milad Nasr, Nicholas Carlini with Claude, Anthropic, Khiem Tran, lebr0nli(National Yang Ming Chiao Tung University), Security, Systems Lab, Kenneth Hsu(Palo Alto Networks), Jérôme DJOUDER, Arash Ale Ebrahim(SCy), Dave G., Vamshi Paili, Tony Gorez for Reverse Society@@tonygo_, CVE-2026-1837, impost0r (ret2plt), Nicholas Soh, David Ige(Beryllium Security), Alan Wang, Ailsa Sun, Christopher W. Fletcher, Hovav Shacham, David Kohlbrenner, Riccardo Paccagnella, Andreas Jaegersberger & Ro Achterberg(Nosebeard Labs), Niels Hofmans(TrendAI Zero Day Initiative), Alex Radocea, Gandalf4a(PKU), Anton Pakhunov, Suresh Sundaram, Jiri Ha, Arni Hardarson, Johnny Franks@@0xjohnny, Google Threat Analysis Group, Mihalis Haatainen, Ari Hawking, Ashish Kunwar, Richard Zana, Dhiyanesh Selvaraj@@redroot97, Somair Ansar, popku1337(STAR Labs SG Pte), Billy Jheng Bing Jhong(STAR Labs SG Pte), Pan Zhenpeng@@Peterpan0927(STAR Labs SG Pte), Robert Tran, Aswin kumar Gokulakannan, Csaba Fitzl@@theevilbit(Iru), Ryan Hileman via Xint Code (xint.io), Chris Betz(Talence Security), Ruslan Dautov, Zhongcheng Li (CK01), Atul R V, Omar Cerrito, Ricardo Prado, Ian van der Wurff (ian.nl), Michael DePlante@@izobashi(TrendAI Zero Day Initiative), Asaf Cohen, Ilya Sc. Jowell A., Peter Malone, Jorge Welch, Doron Assness, Andy Koo@@andykoo(Hexens), Adriatik Raci, Abhay Kailasia@@abhay_kailasia(Safran Mumbai India), Brendon Tiszka(Google Project Zero), Seiji Sakurai@@HeapSmasher, Rosyna Keller(Totally Not Malicious Software), Alvin Aries Tapia, XiguaSec, Yiğit Can YILMAZ@@yilmazcanyigit, Robert Tran(STAR Labs SG Pte), Calif.io in collaboration with Claude, Anthropic Research, Chris Betz, Ilya Andr (andrd3v)(RTU MIREA), Ilias Morad (A2nkF)(Voynich Group), Duy Trần@@khanhduytran0, @@hugeBlack, Guy Dor, Wang Yu, CVE-2025-14017, CVE-2025-14819, Kun Peeks@@SwayZGl1tZyyy, Aswin Kumar Gokula Kannan, wdszzml, Atuin Automated Vulnerability Discovery Engine, beist, Prathamesh Walunj@@attahasa, Dan Raviv, Surya Kushwaha(Supernetworks), Robert Tran(Supernetworks), Peter Malone(Supernetworks), Dave G.(Supernetworks), Alex Radocea(Supernetworks), Pan ZhenPeng@@Peterpan0927(STAR Labs SG Pte), Amy (amys.website), YingQi Shi@@Mas0nShi(DBAppSecurity's WeBin lab), David Ige - Beryllium Security

Affected Software

17 affected componentsFixes available
Apple macOS Tahoe<26.5
26.5
Apple iOS<26.5
26.5
Apple iPadOS<26.5
26.5
Apple visionOS<26.5
26.5
Apple tvOS<26.5
26.5
Apple WatchOS<26.5
26.5
Apple iOS<18.7.9
18.7.9
Apple iPadOS<18.7.9
18.7.9
Apple Safari<26.5
26.5
Apple iPadOS<18.7.9
Apple iPadOS>=26.0<26.5
Apple iPhone OS<18.7.9
Apple iPhone OS>=26.0<26.5
Apple macOS>=26.0<26.5
Apple tvOS<26.5
Apple visionOS<26.5
Apple WatchOS<26.5

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. Upgrade

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

    Fixed in 18.7.9
  3. Upgrade

    Upgrade Apple Safari Web Inspector WebCore Style Resolver to a version that resolves this vulnerability.

    Fixed in 26.5
  4. Upgrade

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

    Fixed in iOS 18.7.9
  5. Upgrade

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

    Fixed in iPadOS 18.7.9
  6. Upgrade

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

    Fixed in iOS 26.5
  7. Upgrade

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

    Fixed in iPadOS 26.5
  8. Upgrade

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

    Fixed in macOS Tahoe 26.5
  9. Upgrade

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

    Fixed in tvOS 26.5
  10. Upgrade

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

    Fixed in visionOS 26.5
  11. Upgrade

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

    Fixed in watchOS 26.5
  12. Compensating control

    Because user interaction is required to exploit this vulnerability (the target must visit a malicious page or open a malicious file), reduce exposure by avoiding navigation to untrusted web pages and opening untrusted files.

Event History

May 11, 2026
Data Sourced
via Apple·12:00 AM
DescriptionWeaknessAffected Software
Updated
via Apple·12:00 AM
DescriptionWeakness
Updated
via Apple·12:00 AM
Affected Software
Updated
via Apple·12:00 AM
DescriptionWeaknessAffected Software
CVE Published
via MITRE·08:07 PM
Data Sourced
via MITRE·08:07 PM
DescriptionWeakness
Data Sourced
via NVD·09:18 PM
DescriptionSeverityWeaknessAffected Software
May 12, 2026
Advisory Published
via ZDI·12:00 AM
Data Sourced
via ZDI·12:00 AM
DescriptionSeverityAffected Software
May 13, 2026
Updated
via Apple·12:00 AM
DescriptionWeaknessAffected Software
Jun 2, 2026
Data Sourced
via Red Hat·01:41 PM
DescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

Frequently Asked Questions

1

What is the severity of CVE-2026-28955?

The severity of CVE-2026-28955 is considered high due to its potential to allow attackers to exploit multiple issues including out-of-bounds read, buffer overflow, and permission-related vulnerabilities.

2

How do I fix CVE-2026-28955?

To fix CVE-2026-28955, you must update your affected Apple devices to the latest software version, specifically version 26.5 or above.

3

What products are affected by CVE-2026-28955?

CVE-2026-28955 affects multiple Apple products including macOS Tahoe, iOS, iPadOS, visionOS, tvOS, and watchOS versions up to 26.5.

4

What types of vulnerabilities are addressed in CVE-2026-28955?

CVE-2026-28955 addresses vulnerabilities such as out-of-bounds reads, authorization issues, and buffer overflows.

5

Is CVE-2026-28955 present in older versions of Apple software?

Yes, CVE-2026-28955 is present in older software versions prior to 26.5 and 18.7.9 for specific products.

Company

Resources

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