CyberSecBulletin
CVE-2026-86881NVD status: Analyzed

iOS and iPadOS: Improper Certificate Validation

Published Updated By the CyberSecBulletin desk

CVE-2026-86881 is a critical-severity improper certificate validation vulnerability in iOS and iPadOS from Apple, with a CVSS 3.1 base score of 9.1 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists versions 26.7, 27 as the first without the flaw, so updating iOS and iPadOS to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.4% chance of exploitation within 30 days, which is low compared with other CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Update iOS and iPadOS to 26.7 or 27, whichever matches your release line, or a later version.
  2. Update macOS to 15.8 or 26.7 or 27, whichever matches your release line, or a later version.
  3. Update tvOS to 27 or a later version.
  4. Read the advisory on support.apple.com for workarounds and exact fixed builds.
  5. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
AppleiOS and iPadOSbefore 26.7; before 2726.7, 27
ApplemacOSbefore 15.8; before 26.7; before 2715.8, 26.7, 27
AppletvOSbefore 2727
ApplevisionOSbefore 2727
ApplewatchOSbefore 2727
AppleiPadOSbefore 26.726.7
AppleIphone OSbefore 26.726.7

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
NoneAvailability is not affected.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N. Scored by CISA (ADP).

Official description

A certificate validation issue was addressed with improved certificate validation. This issue is fixed in iOS 26.7 and iPadOS 26.7, iOS 27 and iPadOS 27, macOS Golden Gate 27, macOS Sequoia 15.8, macOS Tahoe 26.7, tvOS 27, visionOS 27, watchOS 27. An attacker with a compromised intermediate certificate authority may be able to issue certificates with arbitrary extended key usages.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Certificate Validation

The product does not validate, or incorrectly validates, a certificate.

How developers prevent this class of flaw

  • Certificates should be carefully managed and checked to assure that data are encrypted with the intended owner's public key.
  • If certificate pinning is being used, ensure that all relevant properties of the certificate are fully validated before the certificate is pinned, including the hostname.

More Improper Certificate Validation vulnerabilities (CWE-295)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in iOS and iPadOS

All iOS and iPadOS vulnerabilities

Recent Improper Certificate Validation vulnerabilities

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