CVE-2020-3891

Lock-screen message replies via faulty state management

Published Apr 1, 2020 · Updated Aug 4, 2024

Improper lock-screen authorization in Apple iOS before 13.4 and watchOS before 6.2 allows physically proximate attackers to send message replies. The Messages component applies incorrect state management, accepting a lock-screen reply even when the reply setting is disabled; Apple has not disclosed the responsible code path. Exploitation requires physical access to a locked device, and the documented consequence is limited to sending replies.

CVSS severity2.4
Low
EPSS probability0.30%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper lock-screen authorization in Apple iOS before 13.4 and watchOS before 6.2 allows physically proximate attackers to send message replies. The Messages component applies incorrect state management, accepting a lock-screen reply even when the reply setting is disabled; Apple has not disclosed the responsible code path. Exploitation requires physical access to a locked device, and the documented consequence is limited to sending replies.

The record

CVE
CVE-2020-3891
Published
Apr 1, 2020
Updated
Aug 4, 2024
Vendor
Apple
Product
iOS
Classifications
Unavailable
Attack vector
physical
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 1, 2020CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 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 <iOS 13.4 and iPadOS 13.4

What conditions does exploitation require?

Attack vectorphysical
Required privilegesunauthenticated

What is affected?

Apple · iOSversion=unspecified <iOS 13.4 and iPadOS 13.4
Apple · watchOSversion=unspecified <watchOS 6.2

Published CVSS scores

2.4NIST NVDCVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
2.1NIST NVDAV:L/AC:L/Au:N/C:N/I:P/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)
Vectorphysical
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

No sourced classifications are available.

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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