CVE-2026-121061
Description
An use after free flaw was found in the Modularization 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 prevent dereference of freed object pointers in the Chromium Modularization component during HTML rendering: upgrade to Google Chrome 157.0.8103.38 (or the fixed Chromium builds), which corrects object lifecycle and memory management in the Modularization component to prevent use-after-free memory corruption (details restricted upstream), closing crafted HTML page. Until patched, this is a concern on Chromium and Google Chrome browser deployments on any platform rendering untrusted web content, so Restrict user browsing to trusted web domains and block navigation to unverified or arbitrary remote web content. As a compensating measure, Enable Address Space Layout Randomization to impede reliable redirection to payload or gadget addresses, Enforce non-executable memory via the NX/XD bit to prevent execution of shellcode placed in corrupted heap memory, Deploy binaries built with Full RELRO and PIE to protect relocation tables and harden position independence, and Enable Control Flow Integrity or Shadow Call Stack to restrict hijacking of indirect function calls and virtual method tables. These controls limit blast radius and contain exploitation, but they do not fix the underlying use-after-free memory corruption defect — apply the upstream patch to fully remediate.
Highest-impact CME: CME-101 ASLR (Address Space Layout Randomization) (medium)
Understanding the Weakness (CWE)
Integrity
Technical Impact: Modify Memory
The use of previously freed memory may corrupt valid data, if the memory area in question has been allocated and used properly elsewhere.
Availability
Technical Impact: DoS: Crash, Exit, or Restart
If chunk consolidation occurs after the use of previously freed data, the process may crash when invalid data is used as chunk information.
Confidentiality
Technical Impact: Read Memory
Read operations on freed memory can sometimes leak sensitive information instead of causing a crash
Integrity,Confidentiality,Availability
Technical Impact: Execute Unauthorized Code or Commands
If malicious data is entered before chunk consolidation can take place, it may be possible to take advantage of a write-what-where primitive to execute arbitrary code. If the newly allocated data happens to hold a class, in C++ for example, various function pointers may be scattered within the heap data. If one of these function pointers is overwritten with an address to valid shellcode, execution of arbitrary code can be achieved.
Frequently Asked Questions
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