{"id":"CVE-2026-31705","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: fix out-of-bounds write in smb2_get_ea() EA alignment\n\nsmb2_get_ea() applies 4-byte alignment padding via memset() after\nwriting each EA entry","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: fix out-of-bounds write in smb2_get_ea() EA alignment\n\nsmb2_get_ea() applies 4-byte alignment padding via memset() after\nwriting each EA entry. The bounds check …","severity":"critical","cvss":9.8,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-787"],"vendor":"linux","product":"linux_kernel","affected":["linux_kernel >= 5.15.145, < 5.16","linux_kernel >= 6.1.71, < 6.2","linux_kernel >= 6.6, < 6.6.136","linux_kernel >= 6.7, < 6.12.84","linux_kernel >= 6.13, < 6.18.25","linux_kernel >= 6.19, < 7.0.2"],"patched":["linux_kernel 7.0.2"],"published":"2026-05-01","updated":"2026-10-15","sourceUpdated":"2026-10-15T02:19:18.947","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-31705","references":[{"url":"https://git.kernel.org/stable/c/30010c952077a1c89ecdd71fc4d574c75a8f5617","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/790304c02bf9bd7b8171feda4294d6e62d32ae8f","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/922d48fe8c19f388ffa2f709f33acaae4e408de2","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/98f3de6ef4efbd899348d333f0902dc4ff14380c","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/ddbbc8b2a09dd2cfed90871313e3691ae1db08a2","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/ffbce350c6fd1e99116ea57383b9031717e36d3b","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-784472.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"}],"tags":["nvd","cve.org"],"epss":0.00389,"epssPercentile":0.31287,"ingestedAt":"2026-10-15T03:30:12.867Z","slug":"CVE-2026-31705","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: fix out-of-bounds write in smb2_get_ea() EA alignment\n\nsmb2_get_ea() applies 4-byte alignment padding via memset() after\nwriting each EA entry. The bounds check on buf_free_len is performed\nbefore the value memcpy, but the alignment memset fires unconditionally\nafterward with no check on remaining space.\n\nWhen the EA value exactly fills the remaining buffer (buf_free_len == 0\nafter value subtraction), the alignment memset writes 1-3 NUL bytes\npast the buf_free_len boundary. In compound requests where the response\nbuffer is shared across commands, the first command (e.g., READ) can\nconsume most of the buffer, leaving a tight remainder for the QUERY_INFO\nEA response. The alignment memset then overwrites past the physical\nkvmalloc allocation into adjacent kernel heap memory.\n\nAdd a bounds check before the alignment memset to ensure buf_free_len\ncan accommodate the padding bytes.\n\nThis is the same bug pattern fixed by commit beef2634f81f (\"ksmbd: fix\npotencial OOB in get_file_all_info() for compound requests\") and\ncommit fda9522ed6af (\"ksmbd: fix OOB write in QUERY_INFO for compound\nrequests\"), both of which added bounds checks before unconditional\nwrites in QUERY_INFO response handlers.\n\n## Affected\n\n- `linux_kernel >= 5.15.145, < 5.16`\n- `linux_kernel >= 6.1.71, < 6.2`\n- `linux_kernel >= 6.6, < 6.6.136`\n- `linux_kernel >= 6.7, < 6.12.84`\n- `linux_kernel >= 6.13, < 6.18.25`\n- `linux_kernel >= 6.19, < 7.0.2`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `linux_kernel 7.0.2`","depth":"midnight","depthScore":54,"depthScoreParts":{"impact":53.9,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}