CVE-2021-0391

HIGH

Android - Unauthenticated Account Existence Disclosure via Tapjacking Overlay Attack

Title source: llm
STIX 2.1

Exploitation Summary

EIP tracks 1 public exploit for CVE-2021-0391. PoCs published by nanopathi.

AI-analyzed exploit summary This repository contains performance test cases for Android's autofill framework, specifically targeting CVE-2021-0391. The code includes test cases for autofill functionality but does not contain an actual exploit. It appears to be part of a performance testing framework rather than an exploit PoC.

Description

In onCreate() of ChooseTypeAndAccountActivity.java, there is a possible way to learn the existence of an account, without permissions, due to a tapjacking/overlay attack. This could lead to local escalation of privilege with User execution privileges needed. User interaction is needed for exploitation.Product: AndroidVersions: Android-11 Android-8.1 Android-9 Android-10Android ID: A-172841550

Exploits (1)

nomisec WRITEUP
by nanopathi · poc
https://github.com/nanopathi/framework_base_AOSP10_r33_CVE-2021-0391

This repository contains performance test cases for Android's autofill framework, specifically targeting CVE-2021-0391. The code includes test cases for autofill functionality but does not contain an actual exploit. It appears to be part of a performance testing framework rather than an exploit PoC.

Classification
Writeup 90%
Attack Type
Other
Complexity
Moderate
Reliability
Theoretical
Target: Android Autofill Framework (AOSP10_r33)
No auth needed
Prerequisites: Android development environment · Access to Android Autofill framework
devstral-2 · analyzed Feb 18, 2026 Full analysis →

References (1)

Core 1
Core References

Scores

CVSS v3 7.8
EPSS 0.0066
EPSS Percentile 46.4%
Attack Vector LOCAL
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Details

CWE
CWE-1021
Status published
Products (4)
google/android 8.1
google/android 9.0
google/android 10.0
google/android 11.0
Published Mar 10, 2021
Tracked Since Feb 18, 2026