{"cve":"CVE-2026-53059","nvd":{"published":"2026-06-24T17:17:18.463","modified":"2026-09-04T13:20:04.593","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ndm log: fix out-of-bounds write due to region_count overflow\n\nThe local variable region_count in create_log_context() is declared as\nunsigned int (32-bit), but dm_sector_div_up() returns sector_t (64-bit).\nWhen a device-mapper target has a sufficiently large ti->len with a small\nregion_size, the division result can exceed UINT_MAX. The truncated\nvalue is then used to calculate bitset_size, causing clean_bits,\nsync_bits, and recovering_bits to be allocated far smaller than needed\nfor the actual number of regions.\n\nSubsequent log operations (log_set_bit, log_clear_bit, log_test_bit) use\nregion indices derived from the full untruncated region space, causing\nout-of-bounds writes to kernel heap memory allocated by vmalloc.\n\nThis can be reproduced by creating a mirror target whose region_count\noverflows 32 bits:\n\n  dmsetup create bigzero --table '0 8589934594 zero'\n  dmsetup create mymirror --table '0 8589934594 mirror \\\n    core 2 2 nosync 2 /dev/mapper/bigzero 0 \\\n    /dev/mapper/bigzero 0'\n\nThe status output confirms the truncation (sync_count=1 instead of\n4294967297, because 0x100000001 was truncated to 1):\n\n  $ dmsetup status mymirror\n  0 8589934594 mirror 2 254:1 254:1 1/4294967297 ...\n\nThis leads to a kernel crash in core_in_sync:\n\n  BUG: scheduling while atomic: (udev-worker)/9150/0x00000000\n  RIP: 0010:core_in_sync+0x14/0x30 [dm_log]\n  CR2: 0000000000000008\n  Fixing recursive fault but reboot is needed!\n\nFix by widening the local region_count to sector_t and adding an\nexplicit overflow check before the value is assigned to lc->region_count.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8},"cwes":["CWE-787","CWE-190"],"references":["https://git.kernel.org/stable/c/12bd5b88e91a02785244ff1d20fb157e96e9cdc8","https://git.kernel.org/stable/c/3ec74da927b4e171a6fc0e77b1188ba4d019af51","https://git.kernel.org/stable/c/44ab8875ae4a2842bde2d756bed195d375e0debb","https://git.kernel.org/stable/c/4ec8323b9f0764a14d532b1ae9b87f8a9fecb867","https://git.kernel.org/stable/c/b455903eed4558982be0811f5b7f44f6bbc4ff57"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:41:17.107060303+00:00"},"epss":{"cve":"CVE-2026-53059","score":0.0014,"percentile":0.03368,"date":"2026-11-01"},"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."]}