Use-After-Free Vulnerability in Linux Kernel: TLS Encryption Component

CVE-2026-31533

What is CVE-2026-31533?

A use-after-free vulnerability exists in the TLS encryption component of the Linux kernel, specifically within the tls_do_encryption() function. This issue arises due to improper handling of the -EBUSY error path, resulting in a double cleanup of encryption state. When an encryption request encounters an -EBUSY condition, it is queued, but if an error occurs subsequently in the synchronous error path, the state is incorrectly adjusted again. This ambiguity can lead to a situation where memory can be freed while still pending processing by a callback, potentially allowing for exploitation. A fix has been implemented to prevent this double decrement of the state, enhancing overall stability and security during TLS operations.

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