CVE-2026-121079
Description
A race condition flaw was found in the V8 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 disable JIT compilation using the --jitless flag or enforce V8 engine sandboxing in Chromium browser deployments: upgrade to Google Chrome 157.0.8103.38 (or the fixed Chromium builds), which resolves the race condition in the V8 JavaScript engine during script processing to prevent arbitrary code execution within the sandbox, closing crafted HTML page. Until patched, this is a concern on Chromium browser installations across all supported platforms navigating untrusted web content, so prevent users from visiting untrusted or unvetted web pages hosting arbitrary HTML and JavaScript content. As a compensating measure, disable or strictly restrict JavaScript execution in the browser to prevent scripts from triggering the V8 engine race condition and monitor endpoint behavior to detect post-exploitation activity or potential renderer sandbox escapes. These controls limit blast radius and contain exploitation, but they do not fix the underlying V8 race condition defect — apply the upstream patch to fully remediate.
Highest-impact CME: CME-1309 Script Engine Restriction (Sandbox / Disable) (medium)
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory); DoS: Resource Consumption (Other)
When a race condition makes it possible to bypass a resource cleanup routine or trigger multiple initialization routines, it may lead to resource exhaustion.
Availability
Technical Impact: DoS: Crash, Exit, or Restart; DoS: Instability
When a race condition allows multiple control flows to access a resource simultaneously, it might lead the product(s) into unexpected states, possibly resulting in a crash.
Confidentiality,Integrity
Technical Impact: Read Files or Directories; Read Application Data
When a race condition is combined with predictable resource names and loose permissions, it may be possible for an attacker to overwrite or access confidential data (CWE-59).
Access Control
Technical Impact: Execute Unauthorized Code or Commands; Gain Privileges or Assume Identity; Bypass Protection Mechanism
This can have security implications when the expected synchronization is in security-critical code, such as recording whether a user is authenticated or modifying important state information that should not be influenced by an outsider.
Frequently Asked Questions
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