CVE Catalog

CVE-2026-63910

HighCVSS 7.8
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.15%

5th percentile - higher than 5% of all known CVEs

Summary

A use-after-free (UAF) vulnerability was found in the Linux kernel's dma_buf_fd() function related to a tracepoint. After FD_ADD() returns, the file descriptor becomes live in the descriptor table, allowing another thread to close it before DMA_BUF_TRACE() executes, causing a use-after-free of the dma_buf structure.

Risk Assessment

The vulnerability could cause system crashes (kernel panic) or potentially lead to privilege escalation by exploiting access to freed kernel memory.

Recommendation

Immediately update the Linux kernel to a version containing the fix, which splits FD_ADD() into get_unused_fd_flags() and fd_install() and places the tracepoint between them.

Other vulnerabilities in Linux kernel

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Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: dma-buf: fix UAF in dma_buf_fd() tracepoint Once FD_ADD() returns, the fd is live in the file descriptor table and a thread sharing that table can close() it before DMA_BUF_TRACE() runs. The close drops the last reference, __fput() frees the dma_buf, and the tracepoint then dereferences dmabuf to take dmabuf->name_lock -- slab-use-after-free. Split FD_ADD() back into get_unused_fd_flags() + fd_install() and emit the tracepoint between them. While the fdtable slot is reserved with a NULL file pointer, a racing close() returns -EBADF without entering __fput(), so the dma_buf stays alive across the trace. Same approach as commit 2d76319c4cbb ("dma-buf: fix UAF in dma_buf_put() tracepoint"). This undoes the FD_ADD() conversion done in commit 34dfce523c90 ("dma: convert dma_buf_fd() to FD_ADD()"); FD_ADD() has no place to hook the tracepoint safely.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS