{"id":"CVE-2026-89457","title":"s390/dasd: Guard sysfs discipline callbacks against unallocated private data","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\ns390/dasd: Guard sysfs discipline callbacks against unallocated private data\n\nSeveral sysfs show/store handlers call a discipline callback that\ndereferences device->pri…","severity":"medium","cvss":5.5,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","cvssSource":"vendor","cwe":["CWE-476"],"vendor":"Linux","product":"Linux","affected":["Linux >= c729696bcf8b23450043dd9c9972c15e53419ae4 < 644b666c202cce12ccfcf9ded67089b18f4f7659","Linux >= c729696bcf8b23450043dd9c9972c15e53419ae4 < 4a042d8e5f34282577ece50515cea8bb1246914d","Linux >= c729696bcf8b23450043dd9c9972c15e53419ae4 < bd8b4572528f9604a13bf3c7c2a167f5cf222f72","Linux >= c729696bcf8b23450043dd9c9972c15e53419ae4 < 57db27ccc162afe0726cffec0ae62e410ed2d0e9","Linux >= c729696bcf8b23450043dd9c9972c15e53419ae4 < 536407b272402af679155910d7fdeeb4834eefb9","Linux >= c729696bcf8b23450043dd9c9972c15e53419ae4 < 6452c13646af7c13d7f6668b6690cfb2427e7f7b","Linux >= c729696bcf8b23450043dd9c9972c15e53419ae4 < 449f3bada7a9fad8b8cdf4bb20baf27ee9ca56c5","Linux >= c729696bcf8b23450043dd9c9972c15e53419ae4 < 2a1780f9fc2493bd34c418a0be6fc58943afcecf","Linux 5.3"],"published":"2026-09-11","updated":"2026-10-19","sourceUpdated":"2026-10-19T08:47:06.711Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-89457","references":[{"url":"https://git.kernel.org/stable/c/644b666c202cce12ccfcf9ded67089b18f4f7659"},{"url":"https://git.kernel.org/stable/c/4a042d8e5f34282577ece50515cea8bb1246914d"},{"url":"https://git.kernel.org/stable/c/bd8b4572528f9604a13bf3c7c2a167f5cf222f72"},{"url":"https://git.kernel.org/stable/c/57db27ccc162afe0726cffec0ae62e410ed2d0e9"},{"url":"https://git.kernel.org/stable/c/536407b272402af679155910d7fdeeb4834eefb9"},{"url":"https://git.kernel.org/stable/c/6452c13646af7c13d7f6668b6690cfb2427e7f7b"},{"url":"https://git.kernel.org/stable/c/449f3bada7a9fad8b8cdf4bb20baf27ee9ca56c5"},{"url":"https://git.kernel.org/stable/c/2a1780f9fc2493bd34c418a0be6fc58943afcecf"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89457.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-89457"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2532055"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-89457"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89457"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89457.mbox"}],"tags":["cve.org","csaf","vex","red-hat"],"epss":0.00177,"epssPercentile":0.07155,"ingestedAt":"2026-09-14T15:23:07.453Z","slug":"CVE-2026-89457","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\ns390/dasd: Guard sysfs discipline callbacks against unallocated private data\n\nSeveral sysfs show/store handlers call a discipline callback that\ndereferences device->private, either directly or through the\nDASD_DEFINE_ATTR() macro. During dasd_generic_set_online() the discipline\nis assigned before check_device() allocates device->private, so an\nunprivileged read of one of these world-readable attributes in that window\ndereferences a NULL pointer and panics.\n\nGuard the dereference inside each callback that actually touches\ndevice->private.\n\n## Affected\n\n- `Linux >= c729696bcf8b23450043dd9c9972c15e53419ae4 < 644b666c202cce12ccfcf9ded67089b18f4f7659`\n- `Linux >= c729696bcf8b23450043dd9c9972c15e53419ae4 < 4a042d8e5f34282577ece50515cea8bb1246914d`\n- `Linux >= c729696bcf8b23450043dd9c9972c15e53419ae4 < bd8b4572528f9604a13bf3c7c2a167f5cf222f72`\n- `Linux >= c729696bcf8b23450043dd9c9972c15e53419ae4 < 57db27ccc162afe0726cffec0ae62e410ed2d0e9`\n- `Linux >= c729696bcf8b23450043dd9c9972c15e53419ae4 < 536407b272402af679155910d7fdeeb4834eefb9`\n- `Linux >= c729696bcf8b23450043dd9c9972c15e53419ae4 < 6452c13646af7c13d7f6668b6690cfb2427e7f7b`\n- `Linux >= c729696bcf8b23450043dd9c9972c15e53419ae4 < 449f3bada7a9fad8b8cdf4bb20baf27ee9ca56c5`\n- `Linux >= c729696bcf8b23450043dd9c9972c15e53419ae4 < 2a1780f9fc2493bd34c418a0be6fc58943afcecf`\n- `Linux 5.3`\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 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · updated 2026-10-17 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89457.json)","depth":"sunlit","depthScore":30,"depthScoreParts":{"impact":30.3,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":204207,"id":"CVE-2026-89457","ts":1789490240170,"field":"cvss","old":null,"new":"5.5"},{"seq":204206,"id":"CVE-2026-89457","ts":1789490240170,"field":"severity","old":"none","new":"medium"},{"seq":109564,"id":"CVE-2026-89457","ts":1789183732431,"field":"cvss","old":null,"new":"4.7"},{"seq":109563,"id":"CVE-2026-89457","ts":1789183732431,"field":"severity","old":"none","new":"medium"}]}