{"id":"CVE-2026-74470","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nscsi: scsi_debug: Fix REPORT ZONES alloc_len underflow OOB write\n\nresp_report_zones() sizes the reply buffer from the CDB allocation\nlength","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nscsi: scsi_debug: Fix REPORT ZONES alloc_len underflow OOB write\n\nresp_report_zones() sizes the reply buffer from the CDB allocation\nlength. The v3 fix rounds alloc_len…","severity":"high","cvss":7.8,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-787"],"vendor":"Red Hat","product":"Red Hat Enterprise Linux 9","affected":["enterprise_linux 10","enterprise_linux 6","enterprise_linux 8","enterprise_linux 9"],"published":"2026-08-15","updated":"2026-10-16","sourceUpdated":"2026-10-16T20:17:29.813","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-74470","references":[{"url":"https://git.kernel.org/stable/c/2047ed09bf13453b7d6f9431b112ec07984dd69b","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/495058429ca55ab7fcc21977b63b92907ad68066","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/49e5b25a0b74dbac595f122e5608fdce2918cc4e","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/5d3e1d006bbb543259f9e31824caadbfff6a5465","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/7b615fc139e35c81077046df44725c532f7e2404","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/93dde0bf2f39a0f9f57fd610aa3201ce5b753433","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/d6e6da6bc3b53231fac77ffab428da8173ee729c","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-74470.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-74470"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2517097"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-74470"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-74470"},{"url":"https://kernelcve.org/list/?q=CVE-2026-74470"},{"url":"https://lore.kernel.org/linux-cve-announce/2026081534-CVE-2026-74470-6792@gregkh/T"}],"tags":["nvd","csaf","vex","red-hat","cve.org","score-dispute"],"epss":0.00129,"epssPercentile":0.02551,"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-10-16T18:57:17.506626Z"},"scores":{"nvd":7.8,"vendor":5.5,"cna":7.8},"ingestedAt":"2026-10-16T19:46:24.359Z","slug":"CVE-2026-74470","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nscsi: scsi_debug: Fix REPORT ZONES alloc_len underflow OOB write\n\nresp_report_zones() sizes the reply buffer from the CDB allocation\nlength. The v3 fix rounds alloc_len up with ALIGN() before deriving the\ndescriptor count:\n\n\trep_max_zones = (ALIGN((u64)alloc_len, RZONES_DESC_HD) -\n\t\t\t RZONES_DESC_HD) >> ilog2(RZONES_DESC_HD);\n\tarr_len = (u64)RZONES_DESC_HD * (rep_max_zones + 1);\n\nFor alloc_len in 0xFFFFFFC1..0xFFFFFFFF, ALIGN() rounds up to\n0x100000000, so arr_len is 4 GB. On 32-bit, kzalloc()'s size_t is 32-bit\nand truncates 0x100000000 to 0; kzalloc(0) returns ZERO_SIZE_PTR, which\npasses the !arr check, and desc = arr + 64 is then dereferenced in the\nloop -> out-of-bounds write / panic.\n\nClamp rep_max_zones to devip->nr_zones. The loop already stops at\nsdebug_capacity (after nr_zones zones), so a report can never hold more\nthan nr_zones descriptors; the clamp does not change the report, it only\nbounds arr_len to (nr_zones + 1) * RZONES_DESC_HD, a real device\nproperty that can never reach 0x100000000.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 · no fix planned: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 · updated 2026-10-26 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-74470.json)","depth":"twilight","depthScore":43,"depthScoreParts":{"impact":42.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":230398,"id":"CVE-2026-74470","ts":1793134636082,"field":"cvss","old":"5.5","new":"7.8"},{"seq":230397,"id":"CVE-2026-74470","ts":1793134636082,"field":"severity","old":"medium","new":"high"},{"seq":229401,"id":"CVE-2026-74470","ts":1793019743149,"field":"cvss","old":"7.8","new":"5.5"},{"seq":229400,"id":"CVE-2026-74470","ts":1793019743149,"field":"severity","old":"high","new":"medium"}]}