Quick Look: Google Chrome Cast Use After Free Vulnerability CVE-2026-6317 Enables Remote Code Execution

Introduction

A use after free vulnerability in Google Chrome's Cast component gives remote attackers a path to arbitrary code execution, requiring nothing more than a visit to a malicious webpage. With Chrome holding between 66.7 and 75.23 percent of the desktop browser market, CVE-2026-6317 and its CVSS 8.8 score represent a significant exposure surface for virtually every organization.

Technical Information

CVE-2026-6317 is classified under CWE-416 (Use After Free) and resides in Chrome's Cast component. Cast is responsible for Chrome's media casting functionality, including Chromecast integration, media session management, and device communication. The vulnerability arises because a memory pointer associated with a Cast related object is accessed after the underlying memory has been freed. This dangling pointer creates a window during which an attacker can reclaim the freed memory with controlled data and redirect execution flow.

CVSS Breakdown

CISA ADP assigned a CVSS 3.1 base score of 8.8 with the vector AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H. The key takeaways from this scoring:

Metric	Value	Implication
Attack Vector	Network	Exploitable remotely via a crafted webpage
Attack Complexity	Low	No race conditions or special configurations required
Privileges Required	None	No authentication needed
User Interaction	Required	Victim must visit the malicious page
Impact (C/I/A)	High/High/High	Full compromise of the browser process

Exploitation Flow

Based on the available information, exploitation would proceed as follows:

1. The attacker prepares a specially crafted HTML page that interacts with Chrome's Cast subsystem in a way that triggers the memory management flaw.
2. The victim is lured to the malicious page through phishing, a compromised website, or malicious advertising.
3. The crafted page causes a Cast related object to be freed while a stale reference to it persists in the browser's memory.
4. The attacker's payload reclaims the freed memory region, populating it with controlled data structures.
5. When Chrome dereferences the dangling pointer, execution is redirected to attacker controlled code, achieving arbitrary code execution within the context of the browser process.

No public proof of concept or detailed exploit primitives have been published. The Chromium bug tracker entry (issues.chromium.org/issues/500091052) remains access restricted, which is standard practice. Google typically keeps security bug details locked for approximately 14 weeks or until a majority of users have updated. The exact code changes, likely involving improved lifetime management and pointer validation within Cast's session or device objects, cannot be independently verified from public sources at this time.

Patch Information

Google addressed CVE-2026-6317 through a Stable Channel Update for Desktop published on April 15, 2026. This was the second stable channel security refresh for Chrome 147; the initial 147.0.7727.55/56 release landed on April 7, 2026 to fix 60 other vulnerabilities, while this subsequent update targets additional issues including CVE-2026-6317.

The fix is included in the following versions:

Platform	Fixed Version
Windows	147.0.7727.101 or 147.0.7727.102
macOS	147.0.7727.101 or 147.0.7727.102
Linux	147.0.7727.101
Android	147.0.7727.101

The update is delivered automatically through Chrome's built in update mechanism and can be manually verified by navigating to chrome://settings/help. Users can also trigger the update by opening Chrome, selecting Help, then About Google Chrome. A browser relaunch is required to complete the installation.

Because Chrome's Cast component is part of the core Chromium engine, this vulnerability also impacts other Chromium based browsers (Microsoft Edge, Opera, Brave, Vivaldi, and others). Organizations running any of these browsers should monitor for corresponding upstream patch integrations from those vendors.

Enterprise administrators should leverage mobile device management or endpoint management tools to push this update across all corporate endpoints.

Affected Systems and Versions

The vulnerability affects Google Chrome on desktop platforms running versions prior to the patched release:

Operating System	Vulnerable Versions	Fixed Version
Windows	All versions prior to 147.0.7727.101	147.0.7727.101 or 147.0.7727.102
macOS	All versions prior to 147.0.7727.101	147.0.7727.101 or 147.0.7727.102
Linux	All versions prior to 147.0.7727.101	147.0.7727.101
Android	All versions prior to 147.0.7727.101	147.0.7727.101

Other Chromium based browsers that incorporate the Cast component are also affected until they integrate the upstream Chromium patch.

Vendor Security History

Google maintains a highly active security program through the Chromium security team and operates a Vulnerability Reward Program that provides monetary awards for responsibly disclosed flaws. The vendor demonstrates a rapid patch cadence, frequently releasing Stable Channel updates to address critical and high severity issues.

The threat landscape around Chrome remains active. In March and early April 2026 alone, Google confirmed active in the wild exploitation for several Chrome zero day vulnerabilities, including CVE-2026-3910 and CVE-2026-5281. While CVE-2026-6317 has not been reported as exploited in the wild, the pattern of rapid weaponization of Chrome use after free bugs by threat actors makes timely patching essential.

References

• CVE-2026-6317 Detail, NVD
• CVE Record: CVE-2026-6317
• Chrome Releases: Stable Channel Update for Desktop (April 15, 2026)
• Chromium Issue 500091052
• Google Chrome Multiple Vulnerabilities, HKCERT
• Update Google Chrome, Google Support
• Chromium Security
• Chrome Vulnerability Reward Program Rules
• New Chrome Zero Day CVE-2026-5281 Under Active Exploitation, The Hacker News
• Chrome 147 Patches 60 Vulnerabilities, SecurityWeek