CVE-2026-121174
Description
A missing authorization flaw was found in the BackgroundFetch 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 authorization checks within the BackgroundFetch component to prevent cross-origin policy bypasses: upgrade to Google Chrome 157.0.8103.38+ (or the fixed Chromium builds), which enforces authorization checks in the BackgroundFetch component to uphold web origin policy boundaries, closing crafted HTML page. Until patched, this is a concern on Chromium browser installations across all desktop platforms, so restrict user browsing to trusted sites and prevent loading untrusted or attacker-controlled HTML pages. These controls limit blast radius and contain exploitation, but they do not fix the underlying missing authorization defect — apply the upstream patch to fully remediate.
Understanding the Weakness (CWE)
Confidentiality
Technical Impact: Read Application Data; Read Files or Directories
An attacker could read sensitive data, either by reading the data directly from a data store that is not 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 modify sensitive data, either by writing the data directly to a data store that is not 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 gain privileges by modifying or reading critical data directly, or by accessing privileged functionality.
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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