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Vulnerability record · public intelligence
CVE-2021-31815
UNKNOWN

CVE-2021-31815

Published Apr 28, 2021 · Updated Nov 3, 2026

Severity · CVSSUNKNOWN · Not scored
Known exploitationNot listed
EPSS / likelihood0.13%
QFinch risk scoreNot available

Original summary

Normalized public record · Updated Nov 3, 2026

GAEN (aka Google/Apple Exposure Notifications) through 2021-04-27 on Android allows attackers to obtain sensitive information, such as a user's location history, in-person social graph, and (sometimes) COVID-19 infection status, because Rolling Proximity Identifiers and MAC addresses are written to the Android system log, and many Android devices have applications (preinstalled by the hardware manufacturer or network operator) that read system log data and send it to third parties. NOTE: a news outlet (The Markup) states that they received a vendor response indicating that fix deployment "bega

Publisher and source text is retained separately from QFinch interpretation.

QFinch assessment

GAEN (aka Google/Apple Exposure Notifications) through 2021-04-27 on Android allows attackers to obtain sensitive information, such as a user's location history, in-person social graph, and (sometimes) COVID-19 infection status, because Rolling Proximity Identifiers and MAC addresses are written to the Android system log, and many Android devices have applications (preinstalled by the hardware manufacturer or network operator) that read system log data and send it to third parties. NOTE: a news outlet (The Markup) states that they received a vendor response indicating that fix deployment "began several weeks ago and will be complete in the coming days."

Evidence: public source records

Affected products

Affected scope reported by the available public evidence
Affected package, product or rangeFix status
Consult the referenced vendor advisory for affected versions.Consult source advisory

Matching a version is only one part of assessing exposure. QFinch has not assessed your environment on this public page.

Remediation

Apply the vendor-supported fixed release or mitigation, then verify the affected component is no longer reachable.

  1. Confirm the affected product and reachable code path exist in your environment.
  2. Apply the vendor-supported patch or mitigation from the primary advisory.
  3. Rescan the exact deployed revision and retain verification evidence.
Review primary references

Evidence coverage

FIRST-EPSSCVE-LIST-V5
SSVC priority
LOW
Confidence
Not available
Aliases
None reported

Scores appear only when corresponding evidence exists. Missing data is never interpreted as zero risk.

Sources and record history

  1. themarkup.org ↗
  2. blog.appcensus.io ↗

Record history

Published Apr 28, 2021 · Last refreshed Nov 3, 2026

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