CVE-2026-118315 in Chrome
Summary
by MITRE • 10/28/2026
Improper input validation in SVG in Google Chrome prior to 156.0.8078.73 allowed a remote attacker to potentially execute arbitrary code inside the sandbox via a crafted HTML page. (Chromium security severity: High)
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Analysis
by VulDB Data Team • 10/28/2026
The vulnerability identified as an improper input validation flaw within Scalable Vector Graphics handling in Google Chrome prior to version 156.0.8078.73 represents a significant breach of the browser's sandboxing architecture. This issue stems from insufficient sanitization or boundary checking when processing SVG content embedded within HTML documents. When a remote attacker constructs a malicious webpage containing specially crafted SVG elements, they can exploit this logic error to bypass security constraints that are designed to isolate web content from the underlying operating system and other processes. The core technical flaw lies in the renderer's failure to properly validate specific attributes or nested structures within the SVG markup, allowing data intended for graphical rendering to be interpreted as executable instructions by the browser engine.
From a technical perspective, this vulnerability falls under the category of Improper Input Validation, which is classified as CWE-20 in the Common Weakness Enumeration standard. The attack vector involves delivering malicious content through a web page that the victim visits or is redirected to. Once rendered, the malformed SVG data triggers an out-of-bounds write or use-after-free condition within the graphics processing pipeline. This memory corruption allows the attacker to manipulate control flow pointers or inject shellcode into the browser process space. Because Chrome relies heavily on sandboxing to limit the impact of such exploits, bypassing these restrictions is particularly dangerous as it elevates the privilege level of the executed code from a restricted web context to one with broader system access capabilities.
The operational impact of this vulnerability is severe due to its potential for arbitrary code execution within the browser's sandboxed environment. Although Chrome employs multiple layers of defense including DEP, ASLR, and site isolation, successfully exploiting this flaw could allow an attacker to execute arbitrary commands on the victim's machine with the privileges of the current user. This can lead to full system compromise, data exfiltration, installation of persistent malware, or further lateral movement within a network if the browser is used in a corporate environment. The Chromium security team has classified this issue as High severity, reflecting its potential for remote code execution and the relative ease with which it might be weaponized by threat actors targeting users who visit compromised or maliciously hosted websites.
Mitigation strategies primarily involve updating to Google Chrome version 156.0.8078.73 or later, where these input validation checks have been hardened. For organizations unable to immediately patch all endpoints, implementing strict content security policies can help mitigate the risk by restricting the types of resources that can be loaded and executed within web pages. Additionally, deploying browser isolation solutions or sandboxing tools at the network level can prevent malicious SVG payloads from reaching the client's local rendering engine in a way that allows exploitation. Security teams should also monitor for indicators of compromise associated with drive-by download attacks leveraging this specific vulnerability class to ensure rapid detection and response if an update is delayed.
This incident highlights the critical importance of rigorous input validation in complex parsers like those used for SVG, XML, and other markup languages. The ATT&CK framework categorizes such exploitation techniques under Initial Access via Spearphishing Link or Drive-by Compromise, specifically leveraging software vulnerabilities to gain a foothold on target systems. Continuous monitoring of browser update notifications and enforcing automated patch management policies are essential practices to maintain security posture against evolving web-based attack vectors that exploit rendering engine flaws.