CVE-2026-39877: Buffer Overflow

Published Jul 27, 2026
·
Updated

A memory corruption issue was addressed with improved memory handling. This issue is fixed in macOS Sequoia 15.7.8, macOS Sonoma 14.8.8. An app may be able to disclose kernel memory.

Other sources

Accounts. A parsing issue in the handling of directory paths was addressed with improved path validation.

— Apple

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

— Apple

apache. This is a vulnerability in open source code and Apple Software is among the affected projects. The CVE-ID was assigned by a third party. Learn more about the issue and CVE-ID at cve.org.

— Apple

APFS. The issue was addressed with improved memory handling.

— Apple

App Store. This issue was addressed with improved checks.

— Apple

Credit

Юлия Мерцалова, Peter Malone, Rahul Raj, Pinak Oza, Robert Mindo, an anonymous researcher, tamdao, Franco Belman at Blackwing Intelligence, Nicolas Rabrenovic, Irvin Wang, impost0r (ret2plt), David Ige - Beryllium Security, 이재영, Pavan Nallamothu, Jared Reyes, John Lussier, Seonung Park, ALTV!ST (altvi.st/), Dun, YingQi Shi@@Mas0nShi(DBAppSecurity's WeBin lab), Andreas Jaegersberger & Ro Achterberg(Nosebeard Labs), Richard Zana, Nathaniel Oh@@calysteon, Daniel Williams, Gergely Kalman@@gergely_kalman, Anonymous(TrendAI Zero Day Initiative), Mathis Mansière, Csaba Fitzl@@theevilbit(Iru), James Duffy@@0x4A616D657344, Matthew Schneider, XBreach.ai(Nosebeard Labs), Dallas Dubs(Nosebeard Labs), Aaron Grattafiori - NVIDIA AI Red Team, CVE-2026-3784, CVE-2026-3783, HvxyZLF, Lance Cain - Offensive Security Engineer, SpecterOps Inc., Jonathan Bar Or@@yo_yo_yo_jbo, Anthony Laou Hine Tsuei@@anarcheuz, Gil Portnoy & Henry, Ayaan Ahmad, Hyunwoo Kim@@v4bel, erdene-och Byambabayar, Niels Hofmans, Manuel Fernandez (Stackhopper Security), Stanislav Jelezoglo(Positive Technologies), Ilya Andr (andrd3v)(Positive Technologies), Redon Gashi, Trung Nguyen@@everping(CyStack), Dave G., Atul R V & Ashmit Sharma, Hcamael, 章鱼哥 （aipyaipy.com）@@aipy, Aswin Kumar Gokulakannan, Surya Narayan Kushwaha, Cem Onat Karagun, Tristan Madani@@TristanInSec(Talence Security), Jonathan Alush-Aben, Arni Hardarson, Michael DePlante@@izobashi(TrendAI Zero Day Initiative), Gandalf4a(PKU), Anton Pakhunov, PETOWORKS의 Bugeun Choi@@Bugeun, Geonha Lee@@leegn4a, Dhiyanesh Selvaraj@@redroot97, hxr1(STAR Labs SG Pte), Hiroki Imai (LAC Co.(STAR Labs SG Pte), Ltd.)(STAR Labs SG Pte), Billy Jheng Bing Jhong(STAR Labs SG Pte), Pan Zhenpeng@@Peterpan0927(STAR Labs SG Pte), Ashish Kunwar, Igor Ushakov, Ryan Hileman via Xint Code (xint.io), Adam Doupé(ASU SEFCOM), f0r(MurphySec), Mahmoud Abdelmoniem(ThreatBook), Feng Xue(ThreatBook), XGPT(ThreatBook), Wang Yu, Lyutoon, Hiroki Imai (LAC Co., Ltd.), Fábio Luís@@scanpt, DARKNAVY@@DarkNavyOrg, Gor Aleksanyan, Michal Kosiorek, Eddy Tsalolikhin, Asjid Kalam@@odinshell, Hyunwoo Kim@@v4bel(ThreatBook), Wang Yu(STAR Labs SG Pte), Ernesto Martínez García, Calif Research, Ji'an Zhou, Mingxuan Yang, Ye Zhang, Ye Zhang@@VAR10CK(Baidu Security), Vladislav Shevchenko (Positive Technologies)(STAR Labs SG Pte), Pasquale Scola(STAR Labs SG Pte), Lukas Gerlach, Kirin@@Pwnrin(Fudan University), LFY@@secsys(Fudan University), Ruslan Dautov, CVE-2026-4424, Prathamesh Walunj, Amy (amys.website), Atul R V, Daisuke Hatakeyama Research)@@SYZD, Richard Zana(Nosebeard Labs), wh0am1i, stratan@@5tratan, Robert Tran, Mickey Jin@@patch1t, Dan Raviv, Koh M. Nakagawa@@tsunek0h(FFRI Security Inc), Matej Moravec@@MacejkoMoravec, Sindre Sorhus, Francisco Knabe, Hcamael(Stripe), 章鱼哥 （aipyaipy.com）@@aipy(Stripe), JC Alvarado(Stripe), Jacob Hazak, @@pixiepointsec, Asaf Cohen, Junming C.(Chapoly1305), Vivek Dhar, ASI (RM) in Border Security Force, FTR HQ BSF Kashmir, Claudio Bozzato(Cisco Talos), Francesco Benvenuto(Cisco Talos), Calif.io in collaboration with Claude, Anthropic Research, Kitten Food, Tien-Chih Lin(CyCraft Technology), Bruce Dang(Calif), Adam Franke(CyStack), yk lin@@pixiepointsec, wdszzml(Bynar), Atuin Automated Vulnerability Discovery Engine(Bynar), Alfredo Pesoli@@__rev(Bynar)

Affected Software

2 affected componentsFixes available
Apple macOS Sequoia<15.7.8
15.7.8
Apple macOS Sonoma<14.8.8
14.8.8

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 15.7.8
  2. Upgrade

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

    Fixed in 14.8.8
  3. Upgrade

    Upgrade macOS Sequoia to a version that resolves this vulnerability.

    Fixed in 15.7.8
  4. Upgrade

    Upgrade macOS Sonoma to a version that resolves this vulnerability.

    Fixed in 14.8.8

Event History

Jul 27, 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·08:13 PM
Data Sourced
via MITRE·08:13 PM
DescriptionWeakness
Data Sourced
via NVD·09:16 PM
DescriptionSeverityWeakness

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-2026-39877?

The severity of CVE-2026-39877 is rated high with a CVSS score of 7.8.

2

How do I fix CVE-2026-39877?

CVE-2026-39877 can be fixed by updating to macOS Sequoia 15.7.8 or macOS Sonoma 14.8.8.

3

What type of vulnerability is CVE-2026-39877?

CVE-2026-39877 is a memory corruption vulnerability that involves issues such as buffer overflow and input validation.

4

What potential risks does CVE-2026-39877 pose?

CVE-2026-39877 may allow an application to disclose kernel memory, which can compromise system security.

5

When was CVE-2026-39877 published?

CVE-2026-39877 was published on July 27, 2026.

Company

Resources

Contact

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