CVE-2023-40385Network attack vector

DNS-query disclosure through undisclosed relay flaw

Published Jan 10, 2024 · Updated Jun 17, 2025

Information disclosure in WebKit before iOS 17, iPadOS 17, macOS 14, and Safari 17 allows remote attackers to view leaked DNS queries. Apple identifies WebKit as the locus and says vulnerable code was removed, but has not disclosed that code's wrong operation or the triggering content. Exploitation requires Private Relay to be enabled and user interaction; the bounded consequence is disclosure of requested domain names.

CVSS severity6.5
Medium
EPSS probability0.60%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Information disclosure in WebKit before iOS 17, iPadOS 17, macOS 14, and Safari 17 allows remote attackers to view leaked DNS queries. Apple identifies WebKit as the locus and says vulnerable code was removed, but has not disclosed that code's wrong operation or the triggering content. Exploitation requires Private Relay to be enabled and user interaction; the bounded consequence is disclosure of requested domain names.

The record

CVE
CVE-2023-40385
Published
Jan 10, 2024
Updated
Jun 17, 2025
Vendor
Apple
Product
iOS and iPadOS
Classifications
CWE-200, T1040
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 10, 2024CVE publishedPublication date reported by the CVE source.
  2. Jun 17, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=unspecified <17

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Apple · iOS and iPadOSversion=unspecified <17
Apple · Safariversion=unspecified <17
Apple · macOSversion=unspecified <14

Published CVSS scores

6.5CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
6.5NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-200Exposure of Sensitive Information to an Unauthorized Actor
T1040Network Sniffing

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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