CVE-2026-63796
Description
A flaw was found in the Linux kernel's Oracle Cluster File System 2 (ocfs2). A local attacker could craft a malicious group bitmap descriptor that claims a size exceeding the physically allocated bitmap bytes. This improper input validation allows subsequent operations to read or write beyond the intended memory region, leading to a use-after-free vulnerability. This can result in a system crash (denial of service) or potentially lead to arbitrary code execution.
Understanding the Weakness (CWE)
Confidentiality
Technical Impact: Read Memory
If the expired pointer is used in a read operation, an attacker might be able to control data read in by the application.
Availability
Technical Impact: DoS: Crash, Exit, or Restart
If the expired pointer references a memory location that is not accessible to the product, or points to a location that is "malformed" (such as NULL) or larger than expected by a read or write operation, then a crash may occur.
Integrity,Confidentiality,Availability
Technical Impact: Execute Unauthorized Code or Commands
If the expired pointer is used in a function call, or points to unexpected data in a write operation, then code execution may be possible.
Frequently Asked Questions
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