CVE-2026-86922

A flaw was found in WebKitGTK. Due to a type confusion issue—where the application misinterprets an object's data type in memory—processing maliciously crafted web content can lead to memory corruption. A remote attacker could exploit this vulnerability to achieve arbitrary code execution on the targeted system.

This vulnerability is rated as having an Important severity because successful exploitation can allow an unauthenticated remote attacker to execute arbitrary code within the context of the user running the application, although it requires user interaction such as opening a malicious webpage. In Red Hat Enterprise Linux, WebKitGTK is primarily utilized by graphical desktop applications and browser utilities, meaning typical headless server installations without desktop environments are not exposed by default. The blast radius is constrained to the permissions of the local user running the WebKitGTK-based application or sandboxed process.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

--- CME Mitigation Guidance (2026-10-20) --- 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 or restrict JIT compilation in the browser engine to neutralize the primary vector for type confusion exploitation: upgrade to Safari 27 (or the fixed Webkitgtk builds), which improve state management to prevent object type confusion during web content processing, closing all 2 injection vectors (processing maliciously crafted web content, visiting a malicious website). Until patched, this is a concern on Any platform running applications that process web content with WebKitGTK, so restrict browser navigation and prevent users or applications from processing untrusted web content or visiting unverified websites. As a compensating measure, enable address space layout randomization to make exploitation of corrupted pointers and memory layout resolution more difficult, enforce control flow integrity on indirect branches to prevent execution hijacking after memory corruption, disable or restrict the script engine to prevent processing web content that triggers the type confusion, deploy endpoint detection and response monitoring to catch post-exploitation activity and unexpected process execution, and enforce non-executable memory pages to block code execution within writable heap allocations. These controls limit blast radius and contain exploitation, but they do not fix the underlying type confusion defect — apply the upstream patch to fully remediate.

Highest-impact CME: CME-1309 Script Engine Restriction (Sandbox / Disable) (medium)