CVE-2026-79254 Overview
CVE-2026-79254 is a medium-severity vulnerability in Google Chrome on Android caused by incorrect reference resolution in the CustomTabs component. Versions prior to 152.0.7977.65 are affected. A remote attacker can craft an HTML page that bypasses system access restrictions when a user interacts with it. Chromium's internal security severity rating for this issue is Low.
The flaw is classified under CWE-706: Use of Incorrectly-Resolved Name or Reference. Exploitation requires user interaction but no privileges, and it is delivered over the network through standard web content.
Critical Impact
A remote attacker can bypass Android system access restrictions imposed by Chrome CustomTabs by tricking a user into loading a crafted HTML page, potentially exposing restricted resources or interfaces.
Affected Products
- Google Chrome for Android prior to 152.0.7977.65
- Google Android hosts running vulnerable Chrome builds
- Applications embedding Chrome CustomTabs functionality on Android
Discovery Timeline
- 2026-08-25 - CVE-2026-79254 published to the National Vulnerability Database (NVD)
- 2026-08-27 - Last updated in NVD database
Technical Details for CVE-2026-79254
Vulnerability Analysis
The vulnerability resides in Chrome's CustomTabs implementation on Android. CustomTabs allows native Android applications to embed a Chrome-rendered browsing surface while retaining branding and lifecycle control. The component enforces system access restrictions that prevent web content from reaching privileged Android resources or intents.
Incorrect reference resolution [CWE-706] within CustomTabs allows a crafted HTML page to resolve to an object or scope different from what the security model expected. Because the wrong reference is honored, the browser applies the wrong access policy. This bypasses the access restrictions Chrome normally enforces for content rendered inside a CustomTab.
Exploitation requires user interaction, such as opening a link that launches a CustomTab session. The attack has no confidentiality impact and limited integrity impact per the CVSS metrics, but it undermines an isolation boundary that Android apps rely on.
Root Cause
The root cause is improper name or reference resolution in CustomTabs logic. Chrome resolves an identifier, context, or handle to a target that does not match the intended security scope. Attacker-controlled HTML input influences the resolution and reaches privileged behavior that should have been blocked.
Attack Vector
The attack vector is network-based and requires user interaction. An attacker hosts or delivers a crafted HTML page. When a user opens the page in a CustomTab surface within a vulnerable Chrome for Android build, the malformed reference is resolved and system access restrictions are bypassed. See the Chromium Issue Report for tracking details and the Google Chrome Stable Update advisory for release information.
Detection Methods for CVE-2026-79254
Indicators of Compromise
- Android devices running Chrome versions earlier than 152.0.7977.65
- Unexpected CustomTabs sessions launched from apps that render attacker-controlled URLs
- HTML pages containing anomalous scheme handlers, intent URIs, or reference constructs targeting CustomTabs
Detection Strategies
- Inventory installed Chrome for Android versions across managed mobile fleets and flag any build older than 152.0.7977.65
- Inspect mobile web traffic for suspicious redirect chains that terminate in CustomTabs launches
- Correlate mobile browser telemetry with app intent activity to spot content bypassing expected access controls
Monitoring Recommendations
- Enable managed Google Play or MDM reporting for Chrome version compliance on Android endpoints
- Monitor DNS and proxy logs for HTML delivery paths associated with mobile phishing campaigns
- Track anomalous CustomTabs usage patterns from third-party Android applications that embed browser surfaces
How to Mitigate CVE-2026-79254
Immediate Actions Required
- Update Google Chrome on Android to version 152.0.7977.65 or later through the Google Play Store
- Enforce automatic Chrome updates on managed Android devices via MDM or Android Enterprise policy
- Audit internal Android applications that embed CustomTabs to confirm they open only trusted URLs
Patch Information
Google addressed the issue in Chrome 152.0.7977.65 for Android. Refer to the Google Chrome Stable Update advisory and the Chromium Issue Report for release and tracking information. Applying the vendor patch is the recommended remediation.
Workarounds
- Restrict users from opening untrusted links on Android devices running unpatched Chrome builds
- Use MDM policy to prevent installation or sideloading of apps that launch arbitrary URLs through CustomTabs
- Educate users to avoid interacting with unsolicited links delivered through SMS, email, or messaging apps until Chrome is updated
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
