CVE-2025-39836
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: efi: stmm: Fix incorrect buffer allocation method The communication buffer allocated by setup_mm_hdr() is later on passed to tee_shm_register_kernel_buf(). The latter expects those buffers to be contiguous pages, but setup_mm_hdr() just uses kmalloc(). That can cause various corruptions or BUGs, specifically since commit 9aec2fb0fd5e ("slab: allocate frozen pages"), though it was broken before as well. Fix this by using alloc_pages_exact() instead of kmalloc().
Severity
HIGH
CVSS score
7.8
(v3.1)
Vulnerability status
Modified
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2025-09-16 14:15:51.983000
Last modified
2026-10-19 21:10:00.160000
View original CVE JSON
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"published": "2025-09-16T14:15:51.983",
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"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nefi: stmm: Fix incorrect buffer allocation method\n\nThe communication buffer allocated by setup_mm_hdr() is later on passed\nto tee_shm_register_kernel_buf(). The latter expects those buffers to be\ncontiguous pages, but setup_mm_hdr() just uses kmalloc(). That can cause\nvarious corruptions or BUGs, specifically since commit 9aec2fb0fd5e\n(\"slab: allocate frozen pages\"), though it was broken before as well.\n\nFix this by using alloc_pages_exact() instead of kmalloc()."
},
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"value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nefi: stmm: Corrección del método incorrecto de asignación de búfer\n\nEl búfer de comunicación asignado por setup_mm_hdr() se pasa posteriormente a tee_shm_register_kernel_buf(). Este último espera que esos búferes sean páginas contiguas, pero setup_mm_hdr() simplemente usa kmalloc(). Esto puede causar varias corrupciones o BUGs, específicamente desde el commit 9aec2fb0fd5e ('slab: allocate frozen pages'), aunque ya estaba roto antes también.\n\nSolucione esto utilizando alloc_pages_exact() en lugar de kmalloc()."
}
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