CVE-2026-121060
Description
An incorrect authorization flaw was found in the FileSystem component of the Chromium browser.
Upstream bug(s):
Statement
Red Hat Product Security rates the severity of this flaw as determined by the Google Chrome Security Advisory.
Mitigation
--- CME Mitigation Guidance (2026-11-04) ---
Disclaimer: The following mitigation solutions are provided as a courtesy, pending the application of an official patch. This content was generated utilizing AI tools in conjunction with data from https://cmetaxonomy.org. Customers are advised to independently evaluate and test these temporary mitigations within their own infrastructure.
The highest-value action is to enforce strict virtual filesystem boundaries and directory allowlists within Chromium FileSystem handling to prevent sandbox escapes: upgrade to Google Chrome 157.0.8103.38+ (or the fixed Chromium builds), which corrects authorization checks in the FileSystem component to prevent sandbox escape and out-of-sandbox code execution, closing crafted HTML page. Until patched, this is a concern on systems and users running Chromium on desktop platforms, so warn users against opening untrusted links or HTML attachments from social engineering lures, and restrict browser navigation to authorized domains. As a compensating measure, canonicalize requested file paths to prevent operations from traversing outside designated browser FileSystem sandbox boundaries, restrict host filesystem access from the browser process via Landlock LSM to confine file operations, and monitor endpoint detection and response telemetry for anomalous process spawning or suspicious file writes from browser processes. These controls limit blast radius and contain exploitation, but they do not fix the underlying incorrect authorization flaw — apply the upstream patch to fully remediate.
Highest-impact CME: CME-1301 Path Traversal Prevention (Canonicalization) (medium)
Understanding the Weakness (CWE)
Confidentiality
Technical Impact: Read Application Data; Read Files or Directories
An attacker could bypass intended access restrictions to read sensitive data, either by reading the data directly from a data store that is not correctly restricted, or by accessing insufficiently-protected, privileged functionality to read the data.
Integrity
Technical Impact: Modify Application Data; Modify Files or Directories
An attacker could bypass intended access restrictions to modify sensitive data, either by writing the data directly to a data store that is not correctly restricted, or by accessing insufficiently-protected, privileged functionality to write the data.
Access Control
Technical Impact: Gain Privileges or Assume Identity; Bypass Protection Mechanism
An attacker could bypass intended access restrictions to gain privileges by modifying or reading critical data directly, or by accessing privileged functionality.
Confidentiality,Integrity,Availability
Technical Impact: Execute Unauthorized Code or Commands
An attacker could use elevated privileges to execute unauthorized commands or code.
Availability
Technical Impact: DoS: Crash, Exit, or Restart; DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory); DoS: Resource Consumption (Other)
An attacker could gain unauthorized access to resources on the system and excessively consume those resources, leading to a denial of service.
Frequently Asked Questions
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