Missing Authorization in SiteIsolation in Google Chrome

Publication date: 2026-08-25

Last updated on: 2026-08-25

Assigner: Chrome

Description

Missing authorization in SiteIsolation in Google Chrome prior to 152.0.7977.65 allowed a remote attacker who had compromised the renderer process to bypass site isolation via a crafted PDF file. (Chromium security severity: Medium)

CVSS Scores

EPSS Scores

Probability:
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Meta Information

Published

2026-08-25

Last Modified

2026-08-25

Generated

2026-08-26

AI Q&A

2026-08-26

EPSS Evaluated

N/A

NVD

CVE-2026-78953

Affected Vendors & Products

Vendor	Product	Version / Range
google	chrome	to 152.0.7977.65 (exc)

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-862	The product does not perform an authorization check when an actor attempts to access a resource or perform an action.

Attack-Flow Graph

Executive Summary

This vulnerability is a missing authorization issue in SiteIsolation in Google Chrome versions before 152.0.7977.65. It allows a remote attacker who has already compromised the renderer process to bypass site isolation protections by using a specially crafted PDF file.

Impact Analysis

If exploited, this vulnerability could allow an attacker to access data from other sites or perform actions on behalf of the user across different domains. This could lead to unauthorized data exposure or account takeovers if the attacker tricks the user into opening a malicious PDF.

Mitigation Strategies

Update Google Chrome to version 152.0.7977.65 or later to address the missing authorization issue in SiteIsolation.

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