CVE-2024-2886: Google Chrome Use After Free Vulnerability

CVE-2024-2886 Overview

CVE-2024-2886 is a use-after-free vulnerability in the WebCodecs component of Google Chrome versions prior to 123.0.6312.86. A remote attacker can exploit this flaw by serving a crafted HTML page to a target user, enabling arbitrary read and write operations within the browser process. The Chromium project rated the security severity as High. The flaw is tracked under [CWE-416] (Use After Free) and affects Chrome on all supported desktop platforms, including downstream distributions such as Fedora 38, 39, and 40.

Critical Impact

Successful exploitation allows arbitrary read/write primitives in the renderer process, which attackers can chain with sandbox escapes to compromise the host system.

Affected Products

• Google Chrome prior to 123.0.6312.86
• Fedora 38, 39, and 40 (Chromium package)
• Chromium-based browsers incorporating the vulnerable WebCodecs code

Discovery Timeline

• 2024-03-26 - CVE-2024-2886 published to NVD following the Chrome Stable Channel update
• 2025-03-22 - Last updated in NVD database

Technical Details for CVE-2024-2886

Vulnerability Analysis

The vulnerability resides in the WebCodecs API, which exposes low-level access to audio and video codecs from JavaScript running in the renderer process. WebCodecs manages decoder and encoder objects that wrap native C++ resources, and lifecycle management between the JavaScript bindings and the underlying media buffers is error prone.

A use-after-free occurs when JavaScript triggers a state in which a WebCodecs object frees a backing buffer or codec instance, yet a dangling pointer to that memory remains reachable. Subsequent operations dereference the freed memory, allowing an attacker who controls the reallocation pattern to read or write attacker-chosen data inside the renderer heap.

With arbitrary read/write inside the renderer, attackers typically corrupt object vtables or JIT-mapped pages to gain code execution in the sandboxed renderer. Pairing this primitive with a separate sandbox escape yields full compromise of the user account.

Root Cause

The root cause is improper object lifetime management in WebCodecs [CWE-416]. A reference to a freed media resource is retained and later dereferenced, violating memory safety invariants enforced elsewhere in Blink and the media pipeline.

Attack Vector

Exploitation requires the victim to load a crafted HTML page hosted by the attacker. No authentication is required, but user interaction (visiting the page) is needed. The page issues a sequence of WebCodecs API calls designed to trigger the freed-object reuse and shape the heap for reliable exploitation.

The vulnerability is described in the Chrome Stable Channel Update and the Chromium Issue Tracker Entry. No public proof-of-concept code is available, and the Chromium issue remains access-restricted at the time of writing.

Detection Methods for CVE-2024-2886

Indicators of Compromise

• Chrome renderer process crashes referencing WebCodecs frames, decoders, or media buffers in crash reports
• Browser telemetry showing unexpected child process termination shortly after visiting an unfamiliar domain
• Outbound connections from chrome.exe or chrome to newly registered or low-reputation domains hosting media-heavy HTML payloads

Detection Strategies

• Inventory installed Chrome and Chromium-based browser versions and flag any build earlier than 123.0.6312.86
• Hunt for browser child processes spawning command shells, scripting engines, or LOLBins shortly after navigation events
• Correlate web proxy logs with endpoint process telemetry to identify users visiting attacker-controlled pages that invoke WebCodecs APIs

Monitoring Recommendations

• Forward Chrome crash dumps and browser telemetry into a centralized analytics pipeline for use-after-free signatures
• Monitor for renderer-to-host privilege transitions that could indicate post-exploitation sandbox escape attempts
• Track patch deployment status across managed endpoints and alert on hosts that remain on vulnerable Chrome builds beyond your defined SLA

How to Mitigate CVE-2024-2886

Immediate Actions Required

• Update Google Chrome to version 123.0.6312.86 or later on all Windows, macOS, and Linux endpoints
• Update Chromium packages on Fedora 38, 39, and 40 using the vendor-supplied advisories
• Restart browser sessions after patching so the new binaries are loaded into memory
• Audit Chromium-based browsers (Edge, Brave, Opera, Vivaldi) and apply their corresponding updates that incorporate the upstream fix

Patch Information

Google resolved the issue in the Chrome Stable channel release 123.0.6312.86 and later. Fedora published updated Chromium packages through the package-announce mailing list. See the Chrome Stable Channel Update and the Fedora announcements for Fedora 38, Fedora 39, and Fedora 40.

Workarounds

• Enforce automatic browser updates via enterprise management policies to eliminate version drift
• Restrict access to untrusted websites through proxy filtering or DNS-layer controls while patching is in progress
• Apply site isolation and strict per-site process policies to limit the blast radius of a renderer compromise

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

# Update Chromium on Fedora
sudo dnf upgrade --refresh chromium

# Windows: confirm Chrome auto-update is enabled via Group Policy
reg query "HKLM\SOFTWARE\Policies\Google\Update" /v UpdateDefault