CVE-2020-24722 Information

Description

LICENSE README.md cvefilelist cvelist nvdcve nvdpages.sh scripts test-CVE-2017-1882.markdown test-CVE-2017-18822.markdown tmpvendorlinks DISPUTED LICENSE README.md cvefilelist cvelist nvdcve nvdpages.sh scripts test-CVE-2017-1882.markdown test-CVE-2017-18822.markdown tmpvendorlinks 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.\

CVSS Vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N

Reference

http://packetstormsecurity.com/files/159496/GAEN-Protocol-Metadata-Deanonymization-Risk-Score-Inflation.html http://seclists.org/fulldisclosure/2020/Oct/12 https://blog.google/inside-google/company-announcements/update-exposure-notifications https://github.com/google/exposure-notifications-internals/blob/main/en-risks-and-mitigations-faq.mdadditional-considerations

Attack Complexity

HIGH

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

NONE

Availability Impact

HIGH

Base Score

NONE

Base Severity

5.9