{"cve":"CVE-2020-24721","nvd":{"published":"2020-09-30T18:15:25.193","modified":"2026-06-17T03:06:02.097","status":"Modified","description":"An issue was discovered in the GAEN (aka Google/Apple Exposure Notifications) protocol through 2020-09-29, as used in COVID-19 applications on Android and iOS. It allows a user to be put in a position where he or she can be coerced into proving or disproving an exposure notification, because of the persistent state of a private framework.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:P/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N","score":5.7},"cwes":[],"references":["http://packetstormsecurity.com/files/159419/Corona-Exposure-Notifications-API-Data-Leakage.html","https://blog.google/inside-google/company-announcements/update-exposure-notifications","https://github.com/minvws/nl-covid19-notification-app-coordination/blob/master/CVEs/CVE-2020-24721.txt","https://seclists.org/fulldisclosure/2020/Sep/53","http://packetstormsecurity.com/files/159419/Corona-Exposure-Notifications-API-Data-Leakage.html"],"products":["apple:exposure_notifications","google:exposure_notifications"],"source":"nvd","synced_at":"2026-10-19T21:09:53.489947993+00:00"},"epss":{"cve":"CVE-2020-24721","score":0.00318,"percentile":0.24766,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}