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TI-2020-15179 Aliases CVE-2020-24722GHSA-2gfr-hjcw-mr7q

An issue was discovered in the GAEN (aka Google/Apple Exposure Notifications) protocol…

Priority LOW 31CWE-294Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
High
Impact type
Security bypass
Confidentiality · integrity · availability
None · High · None
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-294.

Summary

An issue was discovered in the GAEN (aka Google/Apple Exposure Notifications) protocol through 2020-10-05, as used in COVID-19 applications on Android and iOS. The encrypted metadata block with a TX value lacks a checksum, allowing bitflipping to amplify a contamination attack. This can cause metadata deanonymization and risk-score inflation. NOTE: the vendor's position is "We do not believe that TX power authentication would be a useful defense against relay attacks.

Why it matters now

EPSS 0.02465 84th percentileScored 2026-11-07
Public exploit Yes 2 exploit referencesTagged by NVD
Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:a:exposure_notifications_project:exposure_notifications:*:*:*:*:*:android:*:*up to 2020-10-05VulnerableExposure Notifications Project
cpe:2.3:a:exposure_notifications_project:exposure_notifications:*:*:*:*:*:iphone_os:*:*up to 2020-10-05VulnerableExposure Notifications Project
  • cpe:2.3:a:exposure_notifications_project:exposure_notifications:*:*:*:*:*:android:*:* Versions up to 2020-10-05 Vulnerable ·Exposure Notifications Project
  • cpe:2.3:a:exposure_notifications_project:exposure_notifications:*:*:*:*:*:iphone_os:*:* Versions up to 2020-10-05 Vulnerable ·Exposure Notifications Project

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2020-24722
  2. 2026-10-03 Alias added: GHSA-2gfr-hjcw-mr7q

References

Exploit 2

Advisory 2

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences