CVE-2026-13843: Google Chrome RCE Vulnerability

CVE-2026-13843 Overview

CVE-2026-13843 is an input validation vulnerability in Google Chrome for iOS versions prior to 150.0.7871.47. The flaw stems from insufficient validation of untrusted input in the Chrome for iOS component. A remote attacker who has already compromised the renderer process can perform a sandbox escape through a crafted HTML page. Google classifies the Chromium security severity as High, and the CVSS 3.1 score is 9.6. The vulnerability is tracked as [CWE-20] Improper Input Validation and requires user interaction to trigger.

Critical Impact
A successful sandbox escape allows an attacker who controls a compromised renderer process to break out of Chrome's security boundary on iOS, extending impact beyond the browser context.

Affected Products

Google Chrome for iOS prior to 150.0.7871.47
Apple iOS devices running vulnerable Chrome builds
Chromium-based components shipped with the affected Chrome for iOS release

Discovery Timeline

2026-06-30 - CVE-2026-13843 published to the National Vulnerability Database (NVD)
2026-07-02 - Last updated in NVD database

Technical Details for CVE-2026-13843

Vulnerability Analysis

The vulnerability resides in Chrome for iOS and involves insufficient validation of untrusted input crossing the renderer-to-browser boundary. Chrome's multi-process architecture isolates untrusted web content in a renderer process. The sandbox limits what a compromised renderer can do, forcing it to communicate with the more privileged browser process through validated interfaces.

When input validation on that boundary is incomplete, an attacker who already controls the renderer can send crafted messages or content that the browser process mishandles. In CVE-2026-13843, a crafted HTML page delivered to a compromised renderer triggers the flawed validation path, enabling a sandbox escape. The exploitation chain requires the attacker to first achieve renderer compromise, typically via a separate memory corruption bug, and then leverage this issue as the second stage.

Root Cause

The root cause is improper input validation [CWE-20] in Chrome for iOS. Trust assumptions made about data originating from the renderer process were not enforced with sufficient validation, allowing malformed or unexpected input to reach code paths that assumed sanitized data.

Attack Vector

The attack vector is network-based with required user interaction. A victim must load a crafted HTML page in a vulnerable Chrome for iOS build. Because the scope is Changed and both confidentiality and integrity impact are High, a successful exploit crosses the sandbox trust boundary and affects components beyond the vulnerable process.

No verified proof-of-concept code is publicly available. Refer to the Chromium Issue Tracker #516869032 for restricted technical details as they are released.

Detection Methods for CVE-2026-13843

Indicators of Compromise

Chrome for iOS process crashes or unexpected termination correlated with visits to untrusted web content
Outbound connections from mobile endpoints to domains hosting suspicious HTML payloads shortly after Chrome launches
Chrome for iOS build strings below 150.0.7871.47 observed in mobile device inventory telemetry

Detection Strategies

Inventory managed iOS devices and flag Chrome installations reporting versions earlier than 150.0.7871.47
Monitor mobile threat defense (MTD) telemetry for anomalous Chrome behavior, including unexpected child process activity or entitlement usage
Correlate browsing telemetry with threat intelligence feeds identifying crafted HTML pages linked to Chromium sandbox escape chains

Monitoring Recommendations

Ingest Chrome update status and version data into your SIEM to alert when devices remain on outdated builds after the patch release
Track EPSS movement for CVE-2026-13843 (currently 0.305%, percentile 22.262) to reprioritize response if exploitation likelihood increases
Review web proxy and DNS logs for iOS user-agents contacting URLs associated with browser exploitation frameworks

How to Mitigate CVE-2026-13843

Immediate Actions Required

Update Google Chrome for iOS to version 150.0.7871.47 or later on all managed and BYOD devices
Push the update through your mobile device management (MDM) platform and enforce compliance policies that block outdated Chrome builds
Advise users to avoid loading untrusted links in Chrome for iOS until the update is confirmed installed

Patch Information

Google released the fix in Chrome for iOS 150.0.7871.47. See the Google Chrome Stable Update advisory for release details. Additional technical context is tracked in Chromium Issue Tracker #516869032.

Workarounds

No vendor-supplied workaround exists; apply the patched Chrome for iOS build as the primary remediation
Temporarily direct users to an alternate up-to-date browser on iOS if patch deployment is delayed
Restrict access to untrusted web content through mobile web filtering policies until all endpoints are updated

bash

# Verify Chrome for iOS version compliance via MDM query
# Example: query installed app versions and flag Chrome builds below 150.0.7871.47
mdm query --bundle-id com.google.chrome.ios --field CFBundleShortVersionString \
  | awk -F',' '$2 < "150.0.7871.47" {print $1" NON-COMPLIANT: "$2}'