{"cve":"CVE-2025-38620","nvd":{"published":"2025-08-22T16:15:35.320","modified":"2026-06-17T09:17:13.900","status":"Analyzed","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nzloop: fix KASAN use-after-free of tag set\n\nWhen a zoned loop device, or zloop device, is removed, KASAN enabled\nkernel reports \"BUG KASAN use-after-free\" in blk_mq_free_tag_set(). The\nBUG happens because zloop_ctl_remove() calls put_disk(), which invokes\nzloop_free_disk(). The zloop_free_disk() frees the memory allocated for\nthe zlo pointer. However, after the memory is freed, zloop_ctl_remove()\ncalls blk_mq_free_tag_set(&zlo->tag_set), which accesses the freed zlo.\nHence the KASAN use-after-free.\n\n zloop_ctl_remove()\n  put_disk(zlo->disk)\n   put_device()\n    kobject_put()\n     ...\n      zloop_free_disk()\n        kvfree(zlo)\n  blk_mq_free_tag_set(&zlo->tag_set)\n\nTo avoid the BUG, move the call to blk_mq_free_tag_set(&zlo->tag_set)\nfrom zloop_ctl_remove() into zloop_free_disk(). This ensures that\nthe tag_set is freed before the call to kvfree(zlo).","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-416"],"references":["https://git.kernel.org/stable/c/765761851d89c772f482494d452e266795460278","https://git.kernel.org/stable/c/c7c87046b41a9ef28ee7ac476c369da5b5228bc5"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:07:46.309729541+00:00"},"epss":{"cve":"CVE-2025-38620","score":0.00157,"percentile":0.04813,"date":"2026-10-31"},"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."]}