{"id":"CVE-2026-89765","title":"timers/itimer: Zero-init old itimerval before copy to userspace","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\ntimers/itimer: Zero-init old itimerval before copy to userspace\n\nOn native sparc64, struct __kernel_old_timeval contains a four-byte hole\nafter tv_usec because tv_sec i…","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-201"],"vendor":"Linux","product":"Linux","affected":["Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 6d4b937251386d9c6f968e7802f0cb16a8523772","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 4ea70146ab9376092297eb8b622ef1792797f2cf","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < a17b345daff46fec4af9f1ecbdf350208016dd15","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < bdfda99c5763822a9a888e8af0ad7d9312ffcfe2","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 4c66719dd1e4023c5e3f7d050f1bbefec3dfbeb4","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 2bf5e8f7c9bf4ad3be343a9a6e3e50a34264d25e","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 00ef529a5402f41eb1d227916437e237450719f9","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 18c7d85864e554adc8fad1e8d2e9d2cb6c3911c8","Linux 2.6.12"],"published":"2026-09-11","updated":"2026-10-19","sourceUpdated":"2026-10-19T08:52:18.849Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-89765","references":[{"url":"https://git.kernel.org/stable/c/6d4b937251386d9c6f968e7802f0cb16a8523772"},{"url":"https://git.kernel.org/stable/c/4ea70146ab9376092297eb8b622ef1792797f2cf"},{"url":"https://git.kernel.org/stable/c/a17b345daff46fec4af9f1ecbdf350208016dd15"},{"url":"https://git.kernel.org/stable/c/bdfda99c5763822a9a888e8af0ad7d9312ffcfe2"},{"url":"https://git.kernel.org/stable/c/4c66719dd1e4023c5e3f7d050f1bbefec3dfbeb4"},{"url":"https://git.kernel.org/stable/c/2bf5e8f7c9bf4ad3be343a9a6e3e50a34264d25e"},{"url":"https://git.kernel.org/stable/c/00ef529a5402f41eb1d227916437e237450719f9"},{"url":"https://git.kernel.org/stable/c/18c7d85864e554adc8fad1e8d2e9d2cb6c3911c8"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89765.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-89765"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2532295"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-89765"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89765"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89765.mbox"}],"tags":["cve.org","csaf","vex","red-hat"],"epss":0.00201,"epssPercentile":0.09968,"ingestedAt":"2026-09-14T15:23:07.448Z","slug":"CVE-2026-89765","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\ntimers/itimer: Zero-init old itimerval before copy to userspace\n\nOn native sparc64, struct __kernel_old_timeval contains a four-byte hole\nafter tv_usec because tv_sec is 64-bit while __kernel_suseconds_t is 32-bit.\nput_itimerval() fills only the named fields in a stack-allocated\n__kernel_old_itimerval and copies the entire object to userspace, so\ngetitimer() can expose the two padding holes.\n\nZero-initialize the aggregate before assigning the fields so implicit\npadding is deterministic before it crosses the user/kernel boundary.\n\n## Affected\n\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 6d4b937251386d9c6f968e7802f0cb16a8523772`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 4ea70146ab9376092297eb8b622ef1792797f2cf`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < a17b345daff46fec4af9f1ecbdf350208016dd15`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < bdfda99c5763822a9a888e8af0ad7d9312ffcfe2`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 4c66719dd1e4023c5e3f7d050f1bbefec3dfbeb4`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 2bf5e8f7c9bf4ad3be343a9a6e3e50a34264d25e`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 00ef529a5402f41eb1d227916437e237450719f9`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 18c7d85864e554adc8fad1e8d2e9d2cb6c3911c8`\n- `Linux 2.6.12`\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** · Low · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, 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-2026-89765.json)","depth":"sunlit","depthScore":30,"depthScoreParts":{"impact":30.3,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":208933,"id":"CVE-2026-89765","ts":1790062293806,"field":"cvss","old":"5.3","new":"5.5"},{"seq":204015,"id":"CVE-2026-89765","ts":1789490231054,"field":"cvss","old":null,"new":"5.3"},{"seq":204014,"id":"CVE-2026-89765","ts":1789490231054,"field":"severity","old":"none","new":"medium"},{"seq":147408,"id":"CVE-2026-89765","ts":1789270210793,"field":"cvss","old":null,"new":"5.3"},{"seq":147407,"id":"CVE-2026-89765","ts":1789270210793,"field":"severity","old":"none","new":"medium"},{"seq":109164,"id":"CVE-2026-89765","ts":1789183730562,"field":"cvss","old":null,"new":"5.3"},{"seq":109163,"id":"CVE-2026-89765","ts":1789183730562,"field":"severity","old":"none","new":"medium"}]}