CVE-2018-18359 in Chrome
Summary
by MITRE
Incorrect handling of Reflect.construct in V8 in Google Chrome prior to 71.0.3578.80 allowed a remote attacker to perform an out of bounds memory read via a crafted HTML page.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 08/01/2024
The vulnerability identified as CVE-2018-18359 represents a critical memory safety issue within the V8 JavaScript engine that powers Google Chrome and other Chromium-based browsers. This flaw specifically manifests in the incorrect handling of the Reflect.construct API, which is a built-in JavaScript function designed to enable dynamic object construction through reflection. The vulnerability exists in versions of Chrome prior to 71.0.3578.80, making it a significant concern for users who have not updated their browser installations. The issue stems from improper bounds checking during the execution of Reflect.construct operations, creating a pathway for malicious actors to exploit memory access patterns that should otherwise be protected.
The technical implementation of this vulnerability involves a precise manipulation of JavaScript execution flows that ultimately leads to an out-of-bounds memory read condition. When a malicious webpage invokes Reflect.construct with carefully crafted parameters, the V8 engine fails to properly validate the memory boundaries of the constructed objects. This improper validation allows an attacker to read memory locations that are outside the intended bounds of the allocated memory regions. The flaw operates at the intersection of JavaScript execution semantics and low-level memory management, where the Reflect.construct function's internal implementation does not adequately protect against buffer overread conditions. This type of vulnerability falls under the CWE-125 category of Out-of-bounds Read, which is classified as a serious memory safety issue that can lead to information disclosure or potential code execution.
The operational impact of this vulnerability extends beyond simple information disclosure, as it provides attackers with the ability to extract sensitive data from memory locations that should remain protected. Remote attackers can construct malicious HTML pages that, when loaded in vulnerable browsers, trigger the flawed Reflect.construct handling and subsequently read arbitrary memory contents. This capability can potentially expose sensitive information such as cryptographic keys, user credentials, or other confidential data stored in memory. The attack vector is particularly concerning because it requires no local privileges or user interaction beyond visiting a malicious website, making it a prime target for drive-by download attacks and other remote exploitation techniques. From an ATT&CK framework perspective, this vulnerability maps to techniques involving exploitation of memory corruption flaws and remote code execution through browser-based attacks.
Mitigation strategies for CVE-2018-18359 primarily focus on immediate browser updates to versions that contain the necessary patches and security fixes. Google released Chrome version 71.0.3578.80 with specific fixes addressing the memory handling issues in Reflect.construct operations. Organizations should implement comprehensive patch management policies that ensure all browser installations are kept current with the latest security updates. Additional protective measures include deploying web application firewalls, implementing content security policies, and utilizing browser security features such as sandboxing and strict MIME type checking. Network-based detection mechanisms can also be configured to identify suspicious JavaScript patterns that might indicate attempts to exploit this vulnerability. The vulnerability highlights the importance of maintaining up-to-date software ecosystems and demonstrates how seemingly minor JavaScript API implementations can have significant security implications when not properly validated against memory safety requirements.