CVE-2026-121047
Description
A buffer overflow flaw was found in the Media 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 isolate or restrict untrusted media processing in Chromium to prevent heap memory corruption: upgrade to Google Chrome 157.0.8103.38 (or the fixed Chromium builds), which corrects bounds handling to resolve the heap-based buffer overflow in the Media component during media processing, closing crafted HTML page. Until patched, this is a concern on users visiting untrusted websites or opening untrusted HTML files in Chromium across all platforms, so restrict user access to untrusted web content and avoid opening untrusted local HTML files. As a compensating measure, enable Address Space Layout Randomization to randomize process memory and hinder return-oriented programming after heap corruption, deploy an Endpoint Detection and Response agent to detect anomalous child processes or in-memory shellcode execution, and enforce non-executable memory via the NX or XD bit to block execution of shellcode injected into the heap. These controls limit blast radius and contain exploitation, but they do not fix the underlying heap-based buffer overflow defect — apply the upstream patch to fully remediate.
Highest-impact CME: CME-101 ASLR (Address Space Layout Randomization) (medium)
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Crash, Exit, or Restart; DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory)
Buffer overflows generally lead to crashes. Other attacks leading to lack of availability are possible, including putting the program into an infinite loop.
Integrity,Confidentiality,Availability,Access Control
Technical Impact: Execute Unauthorized Code or Commands; Bypass Protection Mechanism; Modify Memory
Buffer overflows often can be used to execute arbitrary code, which is usually outside the scope of a program's implicit security policy. Besides important user data, heap-based overflows can be used to overwrite function pointers that may be living in memory, pointing it to the attacker's code. Even in applications that do not explicitly use function pointers, the run-time will usually leave many in memory. For example, object methods in C++ are generally implemented using function pointers. Even in C programs, there is often a global offset table used by the underlying runtime.
Integrity,Confidentiality,Availability,Access Control,Other
Technical Impact: Execute Unauthorized Code or Commands; Bypass Protection Mechanism; Other
When the consequence is arbitrary code execution, this can often be used to subvert any other security service.
Frequently Asked Questions
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