CVE-2026-121080
Description
An use after free flaw was found in the Codecs 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 (2026-11-06) ---
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 dereferencing of deallocated memory objects during media processing in the Chromium Codecs component: upgrade to Chromium 157.0.8103.38 (or the fixed Chromium builds), which resolves a use-after-free condition in the Codecs component during media processing, closing crafted HTML page. Until patched, this is a concern on Chromium browser users visiting untrusted web content across all supported platforms, so restrict user navigation to untrusted web pages and limit exposure to unverified media content. As a compensating measure, Enable address space layout randomization to hinder reliable pointer dereferencing during exploitation, Enforce non-executable memory permissions on heap and data pages to prevent direct shellcode execution, Use full RELRO and position-independent executables to randomize code locations and protect relocation tables, Enable control flow integrity to validate indirect call targets against corrupted object vtables, and Deploy endpoint detection and response agents to monitor for anomalous process activity escaping renderer containment. These controls limit blast radius and contain exploitation, but they do not fix the underlying use-after-free 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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