{"cve":"CVE-2025-68231","nvd":{"published":"2025-12-16T14:15:57.473","modified":"2026-10-14T13:10:00.187","status":"Deferred","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmm/mempool: fix poisoning order>0 pages with HIGHMEM\n\nThe kernel test has reported:\n\n  BUG: unable to handle page fault for address: fffba000\n  #PF: supervisor write access in kernel mode\n  #PF: error_code(0x0002) - not-present page\n  *pde = 03171067 *pte = 00000000\n  Oops: Oops: 0002 [#1]\n  CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Tainted: G                T   6.18.0-rc2-00031-gec7f31b2a2d3 #1 NONE  a1d066dfe789f54bc7645c7989957d2bdee593ca\n  Tainted: [T]=RANDSTRUCT\n  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014\n  EIP: memset (arch/x86/include/asm/string_32.h:168 arch/x86/lib/memcpy_32.c:17)\n  Code: a5 8b 4d f4 83 e1 03 74 02 f3 a4 83 c4 04 5e 5f 5d 2e e9 73 41 01 00 90 90 90 3e 8d 74 26 00 55 89 e5 57 56 89 c6 89 d0 89 f7 <f3> aa 89 f0 5e 5f 5d 2e e9 53 41 01 00 cc cc cc 55 89 e5 53 57 56\n  EAX: 0000006b EBX: 00000015 ECX: 001fefff EDX: 0000006b\n  ESI: fffb9000 EDI: fffba000 EBP: c611fbf0 ESP: c611fbe8\n  DS: 007b ES: 007b FS: 0000 GS: 0000 SS: 0068 EFLAGS: 00010287\n  CR0: 80050033 CR2: fffba000 CR3: 0316e000 CR4: 00040690\n  Call Trace:\n   poison_element (mm/mempool.c:83 mm/mempool.c:102)\n   mempool_init_node (mm/mempool.c:142 mm/mempool.c:226)\n   mempool_init_noprof (mm/mempool.c:250 (discriminator 1))\n   ? mempool_alloc_pages (mm/mempool.c:640)\n   bio_integrity_initfn (block/bio-integrity.c:483 (discriminator 8))\n   ? mempool_alloc_pages (mm/mempool.c:640)\n   do_one_initcall (init/main.c:1283)\n\nChristoph found out this is due to the poisoning code not dealing\nproperly with CONFIG_HIGHMEM because only the first page is mapped but\nthen the whole potentially high-order page is accessed.\n\nWe could give up on HIGHMEM here, but it's straightforward to fix this\nwith a loop that's mapping, poisoning or checking and unmapping\nindividual pages.","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/19de79aaea33ee1ea058c8711b3b2b4a7e4decd4","https://git.kernel.org/stable/c/6a13b56537e7b0d97f4bb74e8038ce471f9770d7","https://git.kernel.org/stable/c/a79e49e1704367b635edad1479db23d7cf1fb71a","https://git.kernel.org/stable/c/ea4131665107e66ece90e66bcec1a2f1246cbd41","https://git.kernel.org/stable/c/ec33b59542d96830e3c89845ff833cf7b25ef172"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:17:07.138532058+00:00"},"epss":{"cve":"CVE-2025-68231","score":0.00186,"percentile":0.08099,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}