{"id":"CVE-2026-89489","title":"openrisc: fix arbitrary kernel memory access via or1k_atomic syscall","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nopenrisc: fix arbitrary kernel memory access via or1k_atomic syscall\n\nsys_or1k_atomic() (syscall 244 in the \"or1k\" ABI) takes two user\npointers, v1 and v2, and swaps th…","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","cvssSource":"cna","cwe":["CWE-822"],"vendor":"Linux","product":"Linux","affected":["Linux >= 9d02a4283e9ce4e9ca11ff00615bdacdb0515a1a < bf310718c6fa6adeee06d207a55489546d860e2c","Linux >= 9d02a4283e9ce4e9ca11ff00615bdacdb0515a1a < 497cba0b02e5555d99fe9ee1dc478af743ab7f7a","Linux >= 9d02a4283e9ce4e9ca11ff00615bdacdb0515a1a < 1f2e92e499d863f81df1732af59b4a3559969193","Linux >= 9d02a4283e9ce4e9ca11ff00615bdacdb0515a1a < 574ae2ac2b314aa33498cd2c28add106cbe644f2","Linux >= 9d02a4283e9ce4e9ca11ff00615bdacdb0515a1a < a520e8cac54fb403f3800125b606f55fcad42cb9","Linux >= 9d02a4283e9ce4e9ca11ff00615bdacdb0515a1a < d64a75369cd0f2ee79afcc9d9ca34a3890989379","Linux >= 9d02a4283e9ce4e9ca11ff00615bdacdb0515a1a < b53435c079c78f89f70a62dd5a322cca4e292b34","Linux >= 9d02a4283e9ce4e9ca11ff00615bdacdb0515a1a < 78004e9a87f240df03e2f73120d291763c32e0a7","Linux 3.1"],"published":"2026-09-11","updated":"2026-10-19","sourceUpdated":"2026-10-19T08:47:40.968Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-89489","references":[{"url":"https://git.kernel.org/stable/c/bf310718c6fa6adeee06d207a55489546d860e2c"},{"url":"https://git.kernel.org/stable/c/497cba0b02e5555d99fe9ee1dc478af743ab7f7a"},{"url":"https://git.kernel.org/stable/c/1f2e92e499d863f81df1732af59b4a3559969193"},{"url":"https://git.kernel.org/stable/c/574ae2ac2b314aa33498cd2c28add106cbe644f2"},{"url":"https://git.kernel.org/stable/c/a520e8cac54fb403f3800125b606f55fcad42cb9"},{"url":"https://git.kernel.org/stable/c/d64a75369cd0f2ee79afcc9d9ca34a3890989379"},{"url":"https://git.kernel.org/stable/c/b53435c079c78f89f70a62dd5a322cca4e292b34"},{"url":"https://git.kernel.org/stable/c/78004e9a87f240df03e2f73120d291763c32e0a7"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89489.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-89489"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2532099"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-89489"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89489"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89489.mbox"}],"tags":["cve.org","csaf","vex","red-hat","score-dispute"],"epss":0.00136,"epssPercentile":0.03016,"scores":{"cna":7.8,"vendor":5.5},"ingestedAt":"2026-09-14T15:23:07.452Z","slug":"CVE-2026-89489","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nopenrisc: fix arbitrary kernel memory access via or1k_atomic syscall\n\nsys_or1k_atomic() (syscall 244 in the \"or1k\" ABI) takes two user\npointers, v1 and v2, and swaps the words they point to in hand-written\nassembly.\n\n    l.lwz   r29,0(r4)\n    l.lwz   r27,0(r5)\n    l.sw    0(r4),r27\n    l.sw    0(r5),r29\n\nThe pointers are not checked with access_ok(). The four memory\naccesses also have no exception table entries.\n\nA caller passes a kernel address as either pointer, and the syscall\nreads from and writes to it directly.\n\nThis gives an unprivileged process a kernel read/write primitive. It\noverwrites kernel data such as the sys_call_table, gaining code\nexecution in kernel context.\n\nCheck both pointers before entering the critical section. Add fixups\nfor the four memory accesses so faults on valid but unmapped user\naddresses return -EFAULT.\n\n[shorne@gmail.com: fix comment style]\n\n## Affected\n\n- `Linux >= 9d02a4283e9ce4e9ca11ff00615bdacdb0515a1a < bf310718c6fa6adeee06d207a55489546d860e2c`\n- `Linux >= 9d02a4283e9ce4e9ca11ff00615bdacdb0515a1a < 497cba0b02e5555d99fe9ee1dc478af743ab7f7a`\n- `Linux >= 9d02a4283e9ce4e9ca11ff00615bdacdb0515a1a < 1f2e92e499d863f81df1732af59b4a3559969193`\n- `Linux >= 9d02a4283e9ce4e9ca11ff00615bdacdb0515a1a < 574ae2ac2b314aa33498cd2c28add106cbe644f2`\n- `Linux >= 9d02a4283e9ce4e9ca11ff00615bdacdb0515a1a < a520e8cac54fb403f3800125b606f55fcad42cb9`\n- `Linux >= 9d02a4283e9ce4e9ca11ff00615bdacdb0515a1a < d64a75369cd0f2ee79afcc9d9ca34a3890989379`\n- `Linux >= 9d02a4283e9ce4e9ca11ff00615bdacdb0515a1a < b53435c079c78f89f70a62dd5a322cca4e292b34`\n- `Linux >= 9d02a4283e9ce4e9ca11ff00615bdacdb0515a1a < 78004e9a87f240df03e2f73120d291763c32e0a7`\n- `Linux 3.1`\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 · updated 2026-09-18 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89489.json)","depth":"twilight","depthScore":43,"depthScoreParts":{"impact":42.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":224738,"id":"CVE-2026-89489","ts":1792401511308,"field":"cvss","old":"5.5","new":"7.8"},{"seq":224737,"id":"CVE-2026-89489","ts":1792401511308,"field":"severity","old":"medium","new":"high"},{"seq":206952,"id":"CVE-2026-89489","ts":1789749715272,"field":"cvss","old":"7.8","new":"5.5"},{"seq":206951,"id":"CVE-2026-89489","ts":1789749715272,"field":"severity","old":"high","new":"medium"},{"seq":198009,"id":"CVE-2026-89489","ts":1789384321362,"field":"cvss","old":"7","new":"7.8"},{"seq":183786,"id":"CVE-2026-89489","ts":1789356677385,"field":"cvss","old":"7.8","new":"7"},{"seq":153276,"id":"CVE-2026-89489","ts":1789285349847,"field":"cvss","old":null,"new":"7.8"},{"seq":153275,"id":"CVE-2026-89489","ts":1789285349847,"field":"severity","old":"none","new":"high"},{"seq":147774,"id":"CVE-2026-89489","ts":1789270212237,"field":"cvss","old":null,"new":"7"},{"seq":147773,"id":"CVE-2026-89489","ts":1789270212237,"field":"severity","old":"none","new":"high"},{"seq":109532,"id":"CVE-2026-89489","ts":1789183732308,"field":"cvss","old":null,"new":"7"},{"seq":109531,"id":"CVE-2026-89489","ts":1789183732308,"field":"severity","old":"none","new":"high"}]}