CVE-2021-31815

Name: CVE-2021-31815
Creator: NVD / NIST
Published: 2021-04-28T02:15:07.097+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

LOWCVSS 3.3/10EPSS 0.13%

Last modified Jun 17, 2026

CVE-2021-31815 is a low-severity vulnerability rated 3.3/10 on the CVSS scale. GAEN (aka Google/Apple Exposure Notifications) through 2021-04-27 on Android allows attackers to obtain sensitive information, such as a user's location history, in-person social graph, and (sometimes) COVID-19 infection status, because Rolling Proximity Identifiers and MAC addresses are written to the Android system log, and many Android devices have applications (preinstalled by the hardware manufacturer or network operator) that read system log data and send it to third parties. NOTE: a news outlet (The Markup) states that they received a vendor response indicating that fix deployment "began several weeks ago and will be complete in the coming days.". EPSS estimates a 0.13% chance of exploitation in the next 30 days.

Description

GAEN (aka Google/Apple Exposure Notifications) through 2021-04-27 on Android allows attackers to obtain sensitive information, such as a user's location history, in-person social graph, and (sometimes) COVID-19 infection status, because Rolling Proximity Identifiers and MAC addresses are written to the Android system log, and many Android devices have applications (preinstalled by the hardware manufacturer or network operator) that read system log data and send it to third parties. NOTE: a news outlet (The Markup) states that they received a vendor response indicating that fix deployment "began several weeks ago and will be complete in the coming days."

Metrics

CVSS 3.1

3.3/10

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

EPSS Probability

0.13%

3.0th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-319

Affected Software

Vendor	Product	Versions
Google	Google\/Apple Exposure Notifications	<= 2021-04-27

References

https://blog.appcensus.io/2021/04/27/why-google-should-stop-logging-contact-tracing-data/Exploit, Third Party Advisory
https://themarkup.org/privacy/2021/04/27/google-promised-its-contact-tracing-app-was-completely-private-but-it-wasntExploit, Press/Media Coverage, Third Party Advisory
https://blog.appcensus.io/2021/04/27/why-google-should-stop-logging-contact-tracing-data/Exploit, Third Party Advisory
https://themarkup.org/privacy/2021/04/27/google-promised-its-contact-tracing-app-was-completely-private-but-it-wasntExploit, Press/Media Coverage, Third Party Advisory

Timeline

Published: Apr 28, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-31815?

How severe is CVE-2021-31815?

CVE-2021-31815 has a CVSS score of 3.3/10 (LOW severity). The EPSS model estimates a 0.13% probability of exploitation in the next 30 days.

How do I fix CVE-2021-31815?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-31815?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST