CVE-2026-43490
Description
A flaw was found in ksmbd, a Linux kernel module that provides an in-kernel Server Message Block (SMB) server. A remote attacker could exploit this vulnerability by providing a malformed inheritable Access Control Entry (ACE) within a security descriptor. This could lead to an out-of-bounds read or write operation, potentially causing a denial of service (DoS) or information disclosure. The flaw occurs because the system does not properly validate the length of the Security Identifier (SID) within the ACE during inheritance.
Understanding the Weakness (CWE)
Integrity,Confidentiality,Availability
Technical Impact: Read Memory; Modify Memory; Execute Unauthorized Code or Commands
Buffer overflows often can be used to execute arbitrary code, which is usually outside the scope of a program's implicit security policy. This can often be used to subvert any other security service.
Availability
Technical Impact: Modify Memory; DoS: Crash, Exit, or Restart; DoS: Resource Consumption (CPU)
Buffer overflows generally lead to crashes. Other attacks leading to lack of availability are possible, including putting the program into an infinite loop.
Frequently Asked Questions
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