Vulnerability in Exposure Notifications Project
CVE-2020-24722
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.
EPSS: 0.025 (82.8th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N.
Affected products
- Exposure_notifications_project Exposure_notifications
- N/a — versions n/a
Weakness classification (CWE)
References
- cve@mitre.org (Third Party Advisory, x_refsource_MISC)
- cve@mitre.org (Exploit, Mailing List, Third Party Advisory, x_refsource_MISC)
- cve@mitre.org (Third Party Advisory, x_refsource_MISC)
- cve@mitre.org (Exploit, VDB Entry, Third Party Advisory, x_refsource_MISC)
Frequently asked questions
- What is CVE-2020-24722?
- CVE-2020-24722 is a medium-severity vulnerability in Exposure Notifications Project, classified under Authentication Bypass by Capture-replay. CVSS score: 5.9/10. Published 2020-10-07.
- How severe is CVE-2020-24722?
- Medium severity. CVSS v3 base score is 5.9 out of 10.