CVE-2026-118343
Description
An improper input validation flaw was found in the ReadingList 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 (2026-11-03) ---
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 input validation on all content and URLs processed by the ReadingList component to prevent arbitrary code execution within the browser sandbox: upgrade to Google Chrome 156.0.8078.73 (or the fixed Chromium builds), which enforces proper input validation on content and URLs handled by the ReadingList component, closing crafted HTML page. Until patched, this is a concern on all platforms running Chromium or Google Chrome when navigating to untrusted web content, so warn users against opening untrusted HTML pages or adding unverified links to the reading list. As a compensating measure, enforce strict allowlist-based input validation on content and URLs processed by the ReadingList component to block crafted payloads. These controls limit blast radius and contain exploitation, but they do not fix the underlying improper input validation defect — apply the upstream patch to fully remediate.
Highest-impact CME: CME-1315 Allowlist-Preferred Input Validation (Deny-by-Default Filtering) (medium)
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Crash, Exit, or Restart; DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory)
An attacker could provide unexpected values and cause a program crash or arbitrary control of resource allocation, leading to excessive consumption of resources such as memory and CPU.
Confidentiality
Technical Impact: Read Memory; Read Files or Directories
An attacker could read confidential data if they are able to control resource references.
Integrity,Confidentiality,Availability
Technical Impact: Modify Memory; Execute Unauthorized Code or Commands
An attacker could use malicious input to modify data or possibly alter control flow in unexpected ways, including arbitrary command execution.
Frequently Asked Questions
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