CVE-2021-1756

Contact disclosure via lock-screen state mismanagement

Published Apr 2, 2021 · Updated Aug 3, 2024

Information disclosure in Apple iOS and iPadOS before 14.4 allows physically proximate attackers to view contacts through Phone Keypad. Incorrect lock-screen state management permits the keypad interface to expose private contact details while the device remains locked. Physical possession of an affected device is required; the reported consequence is limited to viewing private contact information.

CVSS severity2.4
Low
EPSS probability0.32%
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 Apple iOS and iPadOS before 14.4 allows physically proximate attackers to view contacts through Phone Keypad. Incorrect lock-screen state management permits the keypad interface to expose private contact details while the device remains locked. Physical possession of an affected device is required; the reported consequence is limited to viewing private contact information.

The record

CVE
CVE-2021-1756
Published
Apr 2, 2021
Updated
Aug 3, 2024
Vendor
Apple
Product
iOS and iPadOS
Classifications
T1636.003
Attack vector
physical
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 2, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record 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 <14.4

What conditions does exploitation require?

Attack vectorphysical
Required privilegesunauthenticated

What is affected?

Apple · iOS and iPadOSversion=unspecified <14.4

Published CVSS scores

2.1NISTAV:L/AC:L/Au:N/C:P/I:N/A:N
2.4NISTCVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:L/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.

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No observations available

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

Weakness, pattern, technique

T1636.003Protected User Data: Contact List

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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