Memory Release Flaw in pam_usb Affects Linux Authentication

CVE-2026-48984

What is CVE-2026-48984?

The pam_usb module for Linux contains a vulnerability that allows sensitive data to remain in memory after it is no longer needed. Specifically, the xfree() function fails to zero out the contents of freed memory buffers, potentially exposing critical data, such as one-time pad bytes, to malicious actors. This issue arises in versions 0.9.1 and earlier, where a system utilizing a use-after-free condition or capable of heap inspection could allow attackers to recover sensitive authentication materials. The vulnerability highlights a significant gap in memory management practices, necessitating remediation efforts to strengthen system security.

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