iOS and iPadOS: Improper Authentication
CVE-2026-20683 is a high-severity improper authentication vulnerability in iOS and iPadOS from Apple, with a CVSS 3.1 base score of 7.1 out of 10. It can be exploited with local access to the system by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. The record lists version 27 as the first without the flaw, so updating iOS and iPadOS to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.19% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update iOS and iPadOS to 27 or a later version.
- Update macOS to 15.8 or 26.7 or 27, whichever matches your release line, or a later version.
- Update visionOS to 27 or a later version.
- Read the advisory on support.apple.com for workarounds and exact fixed builds.
- Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Apple | iOS and iPadOS | before 27 | 27 |
| Apple | macOS | before 15.8; before 26.7; before 27 | 15.8, 26.7, 27 |
| Apple | visionOS | before 27 | 27 |
| Apple | iPadOS | before 27.0 | 27.0 |
| Apple | Iphone OS | before 27.0 | 27.0 |
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
- LocalThe attacker needs local access or must trick a user into running something.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- RequiredA user must take an action such as opening a file or link.
- 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:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N. Scored by CISA (ADP).
Official description
An authentication issue was addressed with improved state management. This issue is fixed in iOS 27 and iPadOS 27, macOS Golden Gate 27, macOS Sequoia 15.8, macOS Tahoe 26.7, visionOS 27. An app may be able to use the Sign In With Apple authentication flow to access the user's Apple Account.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Authentication
When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.
How developers prevent this class of flaw
- Use an authentication framework or library such as the OWASP ESAPI Authentication feature.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Advisories
- support.apple.com/en-us/149034Release Notes
- support.apple.com/en-us/149035Release Notes
- support.apple.com/en-us/149038Release Notes
- support.apple.com/en-us/149042Release Notes
- support.apple.com/en-us/149043Release Notes
Other vulnerabilities in iOS and iPadOS
- 8.8 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
Recent Improper Authentication vulnerabilities
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 8.2 High severity
- 7.3 High severity
- 7.3 High severity
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