{"id":"CVE-2026-80536","title":"xfs: bounds-check buffer log item's dirty bitmap","summary":"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 fo…","severity":"high","cvss":8.4,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","cvssSource":"cna","vendor":"Linux","product":"Linux","affected":["Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < acb4e26295e7f0e685815a3fd3d70bd8329cefa1","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < f3859c35a4fbc1c1c58431f684f808e43696891d","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < f7b5fa83e2c192be922121b764415fa8c7549ea1","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < b7528b42813f02724a78fce1da24d69d1bfc4d38","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 7e32d4eebae6ca24f8a673c107fd7eca1f47afc2","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < f8288214459ead7e87d26e5822f62c14a4f2ed6b","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < edaf5b6bd625356893da20d69a259b34a9de2694","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 813f8136a2ce1fee266d02a7df73db6e8a541604","Linux 2.6.12"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-10-16T19:16:45.666700Z"},"published":"2026-08-26","updated":"2026-10-16","sourceUpdated":"2026-10-16T19:26:25.114Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-80536","references":[{"url":"https://git.kernel.org/stable/c/acb4e26295e7f0e685815a3fd3d70bd8329cefa1"},{"url":"https://git.kernel.org/stable/c/f3859c35a4fbc1c1c58431f684f808e43696891d"},{"url":"https://git.kernel.org/stable/c/f7b5fa83e2c192be922121b764415fa8c7549ea1"},{"url":"https://git.kernel.org/stable/c/b7528b42813f02724a78fce1da24d69d1bfc4d38"},{"url":"https://git.kernel.org/stable/c/7e32d4eebae6ca24f8a673c107fd7eca1f47afc2"},{"url":"https://git.kernel.org/stable/c/f8288214459ead7e87d26e5822f62c14a4f2ed6b"},{"url":"https://git.kernel.org/stable/c/edaf5b6bd625356893da20d69a259b34a9de2694"},{"url":"https://git.kernel.org/stable/c/813f8136a2ce1fee266d02a7df73db6e8a541604"}],"tags":["cve.org"],"epss":0.00142,"epssPercentile":0.03114,"ingestedAt":"2026-10-16T19:46:24.320Z","slug":"CVE-2026-80536","body":"## Overview\n\nIn 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.\n\n## Affected\n\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < acb4e26295e7f0e685815a3fd3d70bd8329cefa1`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < f3859c35a4fbc1c1c58431f684f808e43696891d`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < f7b5fa83e2c192be922121b764415fa8c7549ea1`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < b7528b42813f02724a78fce1da24d69d1bfc4d38`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 7e32d4eebae6ca24f8a673c107fd7eca1f47afc2`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < f8288214459ead7e87d26e5822f62c14a4f2ed6b`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < edaf5b6bd625356893da20d69a259b34a9de2694`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 813f8136a2ce1fee266d02a7df73db6e8a541604`\n- `Linux 2.6.12`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":46,"depthScoreParts":{"impact":46.2,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}