Cyber Resilience

CVE-2025-43429

Memory Safety in Apple Safari ≤ 26.1

Published
04 November 2025
Modified
02 April 2026
CVSS Score v3.1 4.3
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L
EPSS Score 0.014 69th percentile
Risk Priority 35 floored blend · peak EPSS

Summary

CVE-2025-43429 is a medium-severity Improper Restriction of Operations within the Bounds of a Memory Buffer (CWE-119) vulnerability in Apple Safari. Its CVSS base score is 4.3 (Medium).

Operationally, ranked in the top 31% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SI-10 (Information Input Validation) and SI-16 (Memory Protection) — see the control section below for these in your framework.

EU & UK References

Vulnerability Data

A buffer overflow was addressed with improved bounds checking. This issue is fixed in Safari 26.1, iOS 18.7.2 and iPadOS 18.7.2, iOS 26.1 and iPadOS 26.1, macOS Tahoe 26.1, tvOS 26.1, visionOS 26.1, watchOS 26.1. Processing maliciously crafted web content…

more

may lead to an unexpected process crash.

CWE(s)

Related Threats

CVEs Like This One

CVE-2025-43419Same product: Apple Ipados
CVE-2025-43435Same product: Apple Ipados
CVE-2025-43425Same product: Apple Ipados
CVE-2025-31204Same product: Apple Ipados
CVE-2025-31273Same product: Apple Ipados
CVE-2025-31257Same product: Apple Ipados
CVE-2024-27820Same product: Apple Ipados
CVE-2024-54551Same product: Apple Ipados
CVE-2025-46298Same product: Apple Ipados
CVE-2025-31238Same product: Apple Ipados

Affected Assets

apple
safari
≤ 26.1
apple
ipados
≤ 26.1
apple
iphone os
≤ 26.1
apple
tvos
≤ 26.1
apple
visionos
≤ 26.1
apple
watchos
≤ 26.1

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
  • SI-16 Memory Protection
  • SI-10 Information Input Validation
  • SC-39 Process Isolation
Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V17.3.2

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly implements memory protection mechanisms that enforce bounds checking and prevent buffer overflows such as the one described in CVE-2025-43429.

prevent

Requires validation of input size and format, which would have blocked the maliciously crafted web content that triggered the unchecked buffer operation.

prevent

Process isolation confines the effects of a buffer overflow crash in the browser renderer to a single process, limiting broader system impact from the described vulnerability.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices (bounds checking, safe APIs, reviews) directly prevent this class of flaw.

ID.RA-01 partial match
prevents

Vulnerability scanning and code analysis directly surface buffer-boundary flaws.

ID.RA-08 partial match
prevents

Receiving and triaging vulnerability disclosures commonly includes buffer-related reports.

PR.AT-02 partial match
prevents

Developer training on secure coding reduces introduction of memory-buffer errors.

PR.PS-02 partial match
prevents

Patching replaces vulnerable code containing buffer-boundary defects.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

detects

Security testing in development catches out-of-bounds accesses before release, covering most instances of the weakness.

prevents

Secure development lifecycle mandates memory-safety practices that directly prevent buffer-boundary violations.

prevents

Application security requirements can specify memory-safety rules, but do not prescribe implementation details.

prevents

Secure architecture and engineering principles include memory-safe design patterns that mitigate buffer overflows.

prevents

Secure coding standards explicitly forbid unsafe buffer operations, directly eliminating CWE-119.

References