dbcve.org
IpadosOperating system · Apple

CVE-2026-20657

MEDIUM · 6.5 CVSS v3.1 Published 2026-03-25
Fix available
A fix is available. Upgrade to 14.8.5 / 15.7.5 or later.
See remediation →
72/100
Remediation priority · Elevated
Remotely reachable No privileges

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
A buffer overflow issue was addressed with improved memory handling. This issue is fixed in iOS 18.7.7 and iPadOS 18.7.7, iOS 26.4 and iPadOS 26.4, macOS Sequoia 15.7.5, macOS Sonoma 14.8.5, macOS Tahoe 26.4, visionOS 26.4. Parsing a maliciously crafted file may lead to an unexpected app termination.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

A buffer overflow vulnerability exists in the file parsing functionality of multiple Apple operating systems. The issue occurs when parsing a maliciously crafted file, which triggers improper memory handling leading to buffer overflow. This results in unexpected application termination (denial of service).

MitigationApply the security updates provided by Apple: iOS 18.7.7/iPadOS 18.7.7, iOS 26.4/iPadOS 26.4, macOS Sequoia 15.7.5, macOS Sonoma 14.8.5, macOS Tahoe 26.4, and visionOS 26.4. Avoid opening untrusted or files from unverified sources.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
IpadosOperating system
Affected:< 18.7.7
Iphone OsOperating system
Affected:< 18.7.7
macOSOperating system
Affected:>= 14.0, < 14.8.5>= 15.0, < 15.7.5

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify the Apple device and operating system
    Determine whether the device is an iPhone, iPad, or Mac. For iOS/iPadOS, go to Settings > General > About. For macOS, go to Apple menu > About This Mac.
    Affected if N/A - this step identifies the platform to determine which version range applies
  2. Check iOS or iPadOS version
    On iPhone or iPad, go to Settings > General > About and note the version number (e.g., 18.5, 18.7.7, 19.0).
    Affected if If the version is less than 18.7.7 (e.g., 18.5, 18.6.x) the device is affected
  3. Check macOS version
    On Mac, go to Apple menu > About This Mac and note the version number (e.g., 14.5, 15.4, 15.7.5).
    Affected if If the version is 14.0 to 14.8.4, or 15.0 to 15.7.4, the Mac is affected
  4. Assess file parsing exposure
    Identify applications that handle file import or parsing (such as document viewers, media players, or file converters). Note which apps accept files from external sources, email attachments, or web downloads.
    Affected if If untrusted files can be opened by any parsing application on the device, the buffer overflow could be triggered

The environment is affected if the device runs iOS/iPadOS below version 18.7.7, or macOS between 14.0-14.8.4 or 15.0-15.7.4, and can parse files from untrusted sources.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 14.8.5 / 15.7.5 / 18.7.7 or later
Fixed in 14.8.515.7.518.7.7
Interim mitigation

Apply the security updates provided by Apple: iOS 18.7.7/iPadOS 18.7.7, iOS 26.4/iPadOS 26.4, macOS Sequoia 15.7.5, macOS Sonoma 14.8.5, macOS Tahoe 26.4, and visionOS 26.4. Avoid opening untrusted or files from unverified sources.

Recommended fix High confidence

iOS 18.7.7/iPadOS 18.7.7 (or iOS 26.4/iPadOS 26.4 for newer devices), macOS Sonoma 14.8.5, or macOS Sequoia 15.7.5

  1. For iPhone/iPad: Open Settings > General > Software Update and install iOS 18.7.7 or iPadOS 18.7.7 (or later)
  2. For macOS: Open System Settings > General > Software Update and install macOS Sonoma 14.8.5 or macOS Sequoia 15.7.5 (or later)
  3. Alternatively, manually download and install the latest security update from apple.com/support

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Ipados Scoped from the published advisory
  • Consultation1.0 h
  • Implementation2.0 h
  • Testing1.0 h
  • Review / QA1.0 h
5.0 hours of engineering $890
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Scan for this in your stack

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-20657 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data