PT-2020-15832 · Google · Gaen Protocol

Stefan Marsiske · Published 2020-10-06 · Updated 2024-08-04 · CVE-2020-24722

Positive Technologies (AI Summary)

CVSS v3.1

5.9

Medium

Base vector

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

Name of the Vulnerable Software and Affected Versions GAEN protocol (affected versions not specified)

Description An issue was discovered in the GAEN protocol, 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. The vendor's position is that TX power authentication would not be a useful defense against relay attacks.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Exploit

Weakness Enumeration

CWE-294

Related Identifiers

CVE-2020-24722

Affected Products

Gaen Protocol

References · 8

• 🔥 http://seclists.org/fulldisclosure/2020/Oct/12 · Exploit
• 🔥 http://packetstormsecurity.com/files/159496/GAEN-Protocol-Metadata-Deanonymization-Risk-Score-Inflation.html · Exploit
• https://nvd.nist.gov/vuln/detail/CVE-2020-24722 · Security Note
• https://osv.dev/vulnerability/CVE-2020-24722 · Vendor Advisory
• https://github.com/google/exposure-notifications-internals/blob/main/en-risks-and-mitigations-faq.md#additional-considerations · Note
• https://blog.google/inside-google/company-announcements/update-exposure-notifications · Note
• https://t.me/defcon_news/58689 · Telegram Post
• https://t.me/cvenotify/89025 · Telegram Post