CVE-2026-7921: Google Chrome Use After Free Vulnerability

CVE-2026-7921 Overview

CVE-2026-7921 is a use-after-free vulnerability in the Passwords component of Google Chrome prior to version 148.0.7778.96. A remote attacker can exploit the flaw by serving a crafted HTML page to a target user. Successful exploitation allows arbitrary code execution within the renderer process. The Chromium project rates the security severity as High.

The vulnerability is tracked as [CWE-416] (Use After Free) and affects Chrome installations across Windows, macOS, and Linux. User interaction is required, as the victim must visit attacker-controlled web content.

Critical Impact
Remote attackers can execute arbitrary code in the browser process via a crafted HTML page, potentially leading to sandbox-stage compromise of the user's session.

Affected Products

Google Chrome prior to 148.0.7778.96
Microsoft Windows installations of Chrome
Apple macOS and Linux installations of Chrome

Discovery Timeline

2026-05-06 - CVE-2026-7921 published to NVD
2026-05-06 - Last updated in NVD database
2026-05 - Google releases fix in the Stable Channel Update for Desktop (Google Chrome Desktop Update)

Technical Details for CVE-2026-7921

Vulnerability Analysis

The flaw resides in the Passwords component of Google Chrome, which manages credential storage, autofill, and password management UI. A use-after-free condition occurs when the component accesses a heap object after it has been freed. Attackers control the freed memory region by triggering specific allocation patterns from JavaScript or HTML form interactions.

Once the dangling pointer is reused, the attacker can redirect execution flow or corrupt adjacent objects. This typically results in arbitrary code execution within the renderer or browser process boundary.

Exploitation requires the victim to load a malicious page in a vulnerable Chrome build. The attack vector is network-based and does not require prior authentication.

Root Cause

The root cause is improper object lifetime management in the Passwords subsystem. A reference to a heap-allocated object persists after the object's destructor executes. When the component dereferences the stale pointer, controlled data placed in the freed slot is treated as a valid object. Details are tracked in Chromium Issue Report #499062376.

Attack Vector

An attacker hosts a crafted HTML page containing JavaScript that interacts with password forms or autofill prompts. The page triggers allocation, deallocation, and reuse sequences against the vulnerable object. After winning the reuse race, the attacker pivots from memory corruption to control-flow hijacking, leveraging standard Chromium exploitation primitives.

The vulnerability mechanism is described in prose only, as no verified public exploit code is available for CVE-2026-7921. Refer to the Chromium issue tracker for technical context once Google removes the access restriction.

Detection Methods for CVE-2026-7921

Indicators of Compromise

Chrome renderer process crashes referencing the Passwords component or heap-use-after-free signatures
Outbound connections from Chrome processes to unfamiliar domains shortly after credential autofill activity
Unexpected child processes spawned by chrome.exe following navigation to untrusted pages

Detection Strategies

Inventory installed Chrome versions across the fleet and flag any build below 148.0.7778.96
Hunt for browser exploitation patterns such as renderer crashes followed by suspicious process creation chains
Correlate web proxy logs with EDR telemetry to identify users visiting attacker infrastructure delivering crafted HTML payloads

Monitoring Recommendations

Monitor browser version telemetry from endpoint management tooling to confirm patch rollout
Alert on Chrome processes performing anomalous file system writes, registry changes, or token manipulation
Track DNS and HTTP requests to newly registered domains hosting suspicious HTML or JavaScript content

How to Mitigate CVE-2026-7921

Immediate Actions Required

Update Google Chrome to version 148.0.7778.96 or later on all Windows, macOS, and Linux endpoints
Restart browser sessions after the update completes to ensure the patched binaries are loaded
Verify enterprise auto-update policies are enabled and not blocked by group policy or proxy configuration

Patch Information

Google addressed CVE-2026-7921 in the Stable Channel Update for Desktop, shipping Chrome 148.0.7778.96. Administrators should reference the Google Chrome Desktop Update advisory for the full list of fixes and rollout guidance. Chromium-based browsers that consume upstream patches should also be updated once vendor builds incorporate the fix.

Workarounds

Disable Chrome's password autofill and password manager features until patching completes
Enforce strict web filtering to block access to untrusted or newly observed domains
Restrict use of Chrome to managed profiles with site isolation and enhanced safe browsing enabled

bash

# Verify Chrome version on Linux endpoints
google-chrome --version

# Windows: query installed Chrome version via registry
reg query "HKLM\Software\Google\Update\Clients\{8A69D345-D564-463C-AFF1-A69D9E530F96}" /v pv

# macOS: confirm installed version
/Applications/Google\ Chrome.app/Contents/MacOS/Google\ Chrome --version