{"cve":"CVE-2026-80536","nvd":{"published":"2026-08-26T15:17:07.777","modified":"2026-10-16T20:17:58.070","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nxfs: bounds-check buffer log item's dirty bitmap\n\nxlog_recover_do_reg_buffer() replays each dirty region described by a\nbuffer log item's bitmap into the buffer read for that item:\n\n\tmemcpy(xfs_buf_offset(bp, (uint)bit << XFS_BLF_SHIFT),\n\t\titem->ri_buf[i].iov_base,\n\t\tnbits << XFS_BLF_SHIFT);\n\nThe destination offset (bit/nbits, from the logged dirty bitmap) and the\nbuffer size (from the logged blf_len) are both attacker-controlled and\notherwise unrelated, yet the only thing bounding the copy is an ASSERT(),\nwhich compiles away on production kernels. A crafted image logging a\nsmall blf_len together with a bitmap bit past the end of that buffer\ndrives the memcpy() past the buffer's allocation, corrupting adjacent\nkernel heap during mount-time log recovery. This is reachable by anyone\nwho can get a crafted image mounted -- the malicious-filesystem threat\nmodel XFS already guards against elsewhere.\n\nTurn the ASSERT() into a real XFS_IS_CORRUPT() check that aborts recovery\nof the buffer with -EFSCORRUPTED, consistent with the validate-and-fail\nidiom already used in xlog_recover_do_inode_buffer() and\nxfs_dquot_item_recover.c. xlog_recover_do_reg_buffer() therefore becomes\nSTATIC int and its three callers propagate the error.\n\nFound and confirmed with KASAN on a CONFIG_XFS_DEBUG=n build: the crafted\nimage trips a slab-out-of-bounds write before this change and fails\nrecovery cleanly with -EFSCORRUPTED after it.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","score":8.4},"cwes":[],"references":["https://git.kernel.org/stable/c/7e32d4eebae6ca24f8a673c107fd7eca1f47afc2","https://git.kernel.org/stable/c/813f8136a2ce1fee266d02a7df73db6e8a541604","https://git.kernel.org/stable/c/acb4e26295e7f0e685815a3fd3d70bd8329cefa1","https://git.kernel.org/stable/c/b7528b42813f02724a78fce1da24d69d1bfc4d38","https://git.kernel.org/stable/c/edaf5b6bd625356893da20d69a259b34a9de2694"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:50:17.453294893+00:00"},"epss":{"cve":"CVE-2026-80536","score":0.00142,"percentile":0.03445,"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."]}