CVE-2026-63816
Description
A flaw was found in the f2fs (Flash-Friendly File System) component of the Linux kernel. This use-after-free (UAF) vulnerability occurs during garbage collection operations when handling Copy-On-Write (COW) files. A local attacker could exploit this by triggering garbage collection, leading to a premature deallocation of memory. Subsequent access to this freed memory could result in a system crash, causing a Denial of Service (DoS), or potentially lead to privilege escalation.
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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