CVE-2024-23708 Overview
CVE-2024-23708 is a local privilege escalation vulnerability in Google Android's NotificationManagerService.java component. The flaw allows an attacker to suppress the toast notification that informs users when an application accesses clipboard contents. By bypassing this user-facing indicator, a malicious app can silently read sensitive clipboard data without alerting the device owner.
The vulnerability affects Android versions 12.0, 12.1, 13.0, and 14.0. Google addressed the issue in the May 2024 Android Security Bulletin. The weakness is classified under [CWE-451: User Interface (UI) Misrepresentation of Critical Information].
Critical Impact
A malicious local application can silently read clipboard contents — including passwords, two-factor codes, and other sensitive data — without surfacing the standard Android toast notification to the user.
Affected Products
- Google Android 12.0
- Google Android 12.1
- Google Android 13.0 and 14.0
Discovery Timeline
- 2024-05-07 - CVE-2024-23708 published to NVD
- 2024-05-01 - Google releases security patch in the Android Security Bulletin
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2024-23708
Vulnerability Analysis
The vulnerability resides in multiple functions within NotificationManagerService.java, the system service responsible for managing Android notifications, including the toast that appears when an application reads from the system clipboard. Starting with Android 12, Google introduced a privacy indicator that surfaces a toast message stating "App pasted from your clipboard" whenever a foreground or background app accesses ClipboardManager data belonging to another app.
This CVE describes a logic flaw that allows the toast notification to be suppressed under specific conditions. An attacker with a low-privileged local app can exploit the gap to read clipboard contents without triggering the expected user-visible warning. The result is a covert information disclosure channel that defeats one of Android's primary clipboard privacy controls.
Exploitation requires local access through an installed application but does not require user interaction.
Root Cause
The root cause is improper handling of toast notification dispatch paths within NotificationManagerService. Code paths exist where clipboard read events do not reliably trigger the corresponding toast UI element. This is a UI misrepresentation issue under [CWE-451], where security-relevant information is withheld from the user.
Attack Vector
A local attacker installs or compromises an application on the target device. The malicious application invokes clipboard read operations through paths that fail to surface the toast indicator. Sensitive data copied by other apps — credentials, password manager output, one-time codes, cryptocurrency wallet addresses — can then be exfiltrated without the user becoming aware.
Review the Android Source Code Commit for the specific code changes that fix the issue.
Detection Methods for CVE-2024-23708
Indicators of Compromise
- Applications requesting READ_CLIPBOARD access or invoking ClipboardManager.getPrimaryClip() from background services without a legitimate use case.
- Absence of expected clipboard-access toast notifications on unpatched Android 12 through 14 devices when third-party apps are in the foreground.
- Unusual outbound network connections from apps shortly after the user copies sensitive content such as passwords or one-time codes.
Detection Strategies
- Audit installed applications for declarations or runtime use of clipboard APIs in their manifests and runtime behavior.
- Use Android enterprise mobility management (EMM) tooling to flag devices running Android builds older than the May 2024 security patch level.
- Inspect logcat output for ClipboardService access events that are not paired with the corresponding toast dispatch from NotificationManagerService.
Monitoring Recommendations
- Track Android security patch level across the managed device fleet and alert on devices below 2024-05-01.
- Monitor mobile threat defense telemetry for apps exhibiting clipboard scraping behavior, particularly after sensitive copy events.
- Correlate mobile device patch posture with identity and authentication telemetry to identify accounts at elevated risk of credential theft.
How to Mitigate CVE-2024-23708
Immediate Actions Required
- Apply the May 2024 Android security patch (2024-05-01 patch level or later) on all Android 12, 12.1, 13, and 14 devices.
- Enforce minimum patch level policies through mobile device management (MDM) or EMM platforms and quarantine non-compliant devices.
- Remove untrusted or unnecessary applications, especially those requesting broad system or notification-related permissions.
Patch Information
Google published the fix in the Android Security Bulletin May 2024. The corresponding code change is available in the Android Source Code Commit. Device manufacturers ship the fix as part of their May 2024 or later security maintenance releases.
Workarounds
- Avoid copying credentials, multi-factor authentication codes, or other sensitive values to the clipboard on unpatched devices.
- Use password managers with autofill APIs instead of copy and paste workflows, which bypass ClipboardManager entirely.
- Restrict installation of applications to vetted sources and require Google Play Protect to remain enabled.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
