xen: fix UAF in dmabuf_exp_from_pages()
CVE-2025-38595 · published 19 Aug 2025
How serious is it
- Severity: high, CVSS score 7.8 out of 10.
- No exploit prediction (EPSS) score yet.
- Not on the CISA list of exploited vulnerabilities.
- No public exploit in Exploit-DB.
Is your app affected by CVE-2025-38595?
Paste this prompt into Claude Code, Cursor or any AI coding tool: it runs a free Shippable scan of your project and fixes what it finds. Built with Lovable, Bolt or v0? Scan your live app. Or upload your package file.
Who is affected
- Linux Linux: a240d6e42e28c34fdc34b3a98ca838a31c939901 to < ba8bc644f168509c16d48444991de7cfea3f12ec, a240d6e42e28c34fdc34b3a98ca838a31c939901 to < e5907885260401bba300d4d18d79875c05b82651, a240d6e42e28c34fdc34b3a98ca838a31c939901 to < 3edfd2353f301bfffd5ee41066e37320a59ccc2d, a240d6e42e28c34fdc34b3a98ca838a31c939901 to < d59d49af4aeed9a81e673e37c26c6a3bacf1a181
- Linux Linux: 4.19
How to check
- Find out whether you run the affected product and which version, then compare it with the versions above.
How to fix
Copies a prompt for Claude Code, Cursor or Codex that asks it to check whether you run this product.
- Apply the vendor's update or mitigation from the references below. If there is none yet, limit exposure of the affected service until there is.
- If a vulnerable version was live, check your logs and rotate the secrets that server could read.
The advisory
In the Linux kernel, the following vulnerability has been resolved:
xen: fix UAF in dmabuf_exp_from_pages()
[dma_buf_fd() fixes; no preferences regarding the tree it goes through -
up to xen folks]
As soon as we'd inserted a file reference into descriptor table, another
thread could close it. That's fine for the case when all we are doing is
returning that descriptor to userland (it's a race, but it's a userland
race and there's nothing the kernel can do about it). However, if we
follow fd_install() with any kind of access to objects that would be
destroyed on close (be it the struct file itself or anything destroyed
by its ->release()), we have a UAF.
dma_buf_fd() is a combination of reserving a descriptor and fd_install().
gntdev dmabuf_exp_from_pages() calls it and then proceeds to access the
objects destroyed on close - starting with gntdev_dmabuf itself.
Fix that by doing reserving descriptor before anything else and do
fd_install() only when everything had been set up.
Check your whole app
Dependencies are only half of it. Free and read-only: before you push, run npx shippable-dev scan localhost:3000 in your project folder, no account needed. For your live app, you prove it's yours with a one-line tag first.
References
- git.kernel.org/stable/c/ba8bc644f168509c16d48444991de7cfea3f12ec
- git.kernel.org/stable/c/e5907885260401bba300d4d18d79875c05b82651
- git.kernel.org/stable/c/3edfd2353f301bfffd5ee41066e37320a59ccc2d
- git.kernel.org/stable/c/d59d49af4aeed9a81e673e37c26c6a3bacf1a181
- git.kernel.org/stable/c/532c8b51b3a8676cbf533a291f8156774f30ea87
Merged from CVE List. Last updated 25 Oct 2026. All vulnerabilities · RSS · JSON