CVE-2026-43739: An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 26.6 and iPadOS 26.6, macOS Tahoe 26.6, tvOS 26.6, visionOS 26.6, watchOS 26.6.

mediumCVSS 5.5CVE-2026-43739

An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 26.6 and iPadOS 26.6, macOS Tahoe 26.6, tvOS 26.6, visionOS 26.6, watchOS 26.6. An app may be able to cause unexpected system termination.

Details

Source: NVD Recent CVEs (US · database · site)
Severity: medium — CVSS 5.5
Published: 2026-07-27
Last updated: 2026-07-29
Exploitation: Not in CISA KEV at last sync

Original advisory: https://nvd.nist.gov/vuln/detail/CVE-2026-43739

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-437390.13% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 3% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-43739	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

high[NEW] [high] Apple macOS (Tahoe, Sonoma, and Sequoia): Multiple vulnerabilitiescert-bund
medium[NEW] [medium] Apple iOS and iPadOS: Multiple vulnerabilitiescert-bund
unknownNCSC-2026-0267 [1.00] [M/H] Vulnerabilities fixed in Apple MacOSncsc-nl
unknownNCSC-2026-0266 [1.00] [M/H] Vulnerabilities fixed in Apple iOS and iPadOSncsc-nl

Recent advisories for An out-of-bounds write

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

highCVE-2026-34641: Premiere Pro is affected by an out-of-bounds write vulnerability that could result in arbitrar…nvd · 2026-07-31
highCVE-2026-65423: An integer overflow in the UA_Variant arrayDimensions product computation in open62541 may all…nvd · 2026-07-30
criticalCVE-2026-47876: VMware ESX contains an out-of-bounds write vulnerability in the VMXNET3 virtual network adapte…nvd · 2026-07-30
unknownCVE-2026-17544: Attacker-provided inputs to bccomp() could lead to an out-of-bounds write with stack and heap …nvd · 2026-07-30
highCVE-2026-18022: Integer wraparound in IVFFlat index build in pgvector before 0.8.6 allows a database user to w…nvd · 2026-07-29
unknownCVE-2026-12927: CWE-787 Out-of-bounds write vulnerability exists that could cause loss of data or potentially …nvd · 2026-07-29