CVE-2023-5218 in Chrome
Summary
by MITRE • 10/25/2023
Use after free in Site Isolation in Google Chrome prior to 118.0.5993.70 allowed a remote attacker to potentially exploit heap corruption via a crafted HTML page. (Chromium security severity: Critical)
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 05/01/2025
The vulnerability CVE-2023-5218 represents a critical use-after-free flaw in Google Chrome's Site Isolation mechanism, which is a fundamental security feature designed to isolate web content from different origins to prevent cross-site attacks. This vulnerability exists in Chrome versions prior to 118.0.5993.70 and has been classified with a critical severity rating by the Chromium security team, indicating its potential for serious exploitation. Site Isolation is a core component of modern browser security architecture that creates separate processes for different websites, thereby preventing malicious websites from accessing data from other sites through various attack vectors such as cross-site scripting or memory corruption techniques.
The technical flaw manifests as a use-after-free condition within the Site Isolation implementation, where memory that has been freed is still being accessed or referenced by the application. This type of vulnerability occurs when a program continues to use a pointer to memory that has already been deallocated, creating a scenario where subsequent operations on that memory location can lead to unpredictable behavior, memory corruption, or potential code execution. The specific context involves how Chrome handles memory management during the process isolation of web content, particularly when transitioning between different site contexts or when handling certain HTML page structures that trigger the problematic code path.
The operational impact of this vulnerability is significant as it allows remote attackers to potentially exploit heap corruption through a specially crafted HTML page delivered over the internet. Attackers can leverage this flaw to execute arbitrary code on the victim's system with the privileges of the Chrome browser process, potentially leading to full system compromise. The heap corruption aspect means that attackers can manipulate memory layout and potentially overwrite critical data structures or function pointers, enabling them to redirect execution flow or inject malicious code. This vulnerability particularly threatens users who browse the web regularly, as the attack vector requires only visiting a malicious webpage, making it highly practical for widespread exploitation in real-world scenarios.
The vulnerability aligns with CWE-416, which specifically addresses the use of freed memory condition, and represents a classic example of heap-based memory corruption that has been extensively documented in security literature. From an ATT&CK framework perspective, this vulnerability maps to techniques involving code injection and privilege escalation, as it can be used to execute arbitrary code in the context of the browser process. The exploitation chain typically involves crafting HTML content that triggers the specific code path leading to the use-after-free condition, followed by heap spraying or memory manipulation techniques to achieve reliable code execution. Organizations should prioritize immediate patching of affected Chrome versions and consider implementing additional security measures such as sandboxing, content security policies, and web application firewalls to reduce the attack surface and protect against potential exploitation attempts.