{"id":"CVE-2025-38595","title":"xen: fix UAF in dmabuf_exp_from_pages()","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nxen: fix UAF in dmabuf_exp_from_pages()\n\n[dma_buf_fd() fixes; no preferences regarding the tree it goes through -\nup to xen folks]\n\nAs soon as we'd inserted a file refe…","severity":"high","cvss":7.8,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cvssSource":"cna","vendor":"Linux","product":"Linux","affected":["Linux >= a240d6e42e28c34fdc34b3a98ca838a31c939901 < ba8bc644f168509c16d48444991de7cfea3f12ec","Linux >= a240d6e42e28c34fdc34b3a98ca838a31c939901 < e5907885260401bba300d4d18d79875c05b82651","Linux >= a240d6e42e28c34fdc34b3a98ca838a31c939901 < 3edfd2353f301bfffd5ee41066e37320a59ccc2d","Linux >= a240d6e42e28c34fdc34b3a98ca838a31c939901 < d59d49af4aeed9a81e673e37c26c6a3bacf1a181","Linux >= a240d6e42e28c34fdc34b3a98ca838a31c939901 < 532c8b51b3a8676cbf533a291f8156774f30ea87","Linux 4.19"],"published":"2025-08-19","updated":"2026-10-21","sourceUpdated":"2026-10-21T12:37:08.055Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2025-38595","references":[{"url":"https://git.kernel.org/stable/c/ba8bc644f168509c16d48444991de7cfea3f12ec"},{"url":"https://git.kernel.org/stable/c/e5907885260401bba300d4d18d79875c05b82651"},{"url":"https://git.kernel.org/stable/c/3edfd2353f301bfffd5ee41066e37320a59ccc2d"},{"url":"https://git.kernel.org/stable/c/d59d49af4aeed9a81e673e37c26c6a3bacf1a181"},{"url":"https://git.kernel.org/stable/c/532c8b51b3a8676cbf533a291f8156774f30ea87"}],"tags":["cve.org"],"epss":0.00216,"epssPercentile":0.1189,"ingestedAt":"2026-10-21T12:48:53.703Z","slug":"CVE-2025-38595","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nxen: fix UAF in dmabuf_exp_from_pages()\n\n[dma_buf_fd() fixes; no preferences regarding the tree it goes through -\nup to xen folks]\n\nAs soon as we'd inserted a file reference into descriptor table, another\nthread could close it.  That's fine for the case when all we are doing is\nreturning that descriptor to userland (it's a race, but it's a userland\nrace and there's nothing the kernel can do about it).  However, if we\nfollow fd_install() with any kind of access to objects that would be\ndestroyed on close (be it the struct file itself or anything destroyed\nby its ->release()), we have a UAF.\n\ndma_buf_fd() is a combination of reserving a descriptor and fd_install().\ngntdev dmabuf_exp_from_pages() calls it and then proceeds to access the\nobjects destroyed on close - starting with gntdev_dmabuf itself.\n\nFix that by doing reserving descriptor before anything else and do\nfd_install() only when everything had been set up.\n\n## Affected\n\n- `Linux >= a240d6e42e28c34fdc34b3a98ca838a31c939901 < ba8bc644f168509c16d48444991de7cfea3f12ec`\n- `Linux >= a240d6e42e28c34fdc34b3a98ca838a31c939901 < e5907885260401bba300d4d18d79875c05b82651`\n- `Linux >= a240d6e42e28c34fdc34b3a98ca838a31c939901 < 3edfd2353f301bfffd5ee41066e37320a59ccc2d`\n- `Linux >= a240d6e42e28c34fdc34b3a98ca838a31c939901 < d59d49af4aeed9a81e673e37c26c6a3bacf1a181`\n- `Linux >= a240d6e42e28c34fdc34b3a98ca838a31c939901 < 532c8b51b3a8676cbf533a291f8156774f30ea87`\n- `Linux 4.19`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":43,"depthScoreParts":{"impact":42.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}