{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-89489","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-09-11T19:38:34.713Z","datePublished":"2026-09-11T19:43:42.164Z","dateUpdated":"2026-09-14T12:00:24.593Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-09-14T12:00:24.593Z"},"descriptions":[{"lang":"en","value":"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 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]"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - sys_or1k_atomic (syscall 244) is reached only via a local OpenRISC syscall into _sys_call_handler and sys_call_table; there is no network, adjacent-wireless, or physical-device path to the unchecked loads/stores in arch/openrisc/kernel/entry.S.\nAC:L - The attacker fully controls both pointer arguments and the swap is deterministic with no race or KASLR (OpenRISC has none); a published unprivileged PoC on qemu-system-or1k overwrote sys_call_table[174] and obtained uid=0 on every run.\nPR:L - Any unprivileged local process can invoke syscall 244; the handler performs no capable()/ns_capable() check, authentication, or init-namespace root gate before dereferencing the caller-supplied pointers.\nUI:N - The attacking process issues or1k_atomic itself with crafted kernel addresses; no other user must mount a filesystem, open a device, or otherwise interact.\nS:U - This is a standard host-kernel privilege escalation (arbitrary kernel R/W and commit_creds via a hijacked syscall); it does not cross a VM guest/host, IOMMU, or other security-authority boundary.\nC:H - The syscall atomically swaps two 32-bit words at attacker-chosen addresses with no access_ok(), so pairing a kernel pointer with a userspace buffer yields an arbitrary kernel-memory read primitive of any mapped word.\nI:H - The same swap is an arbitrary kernel write; the fix commit documents overwriting sys_call_table to run commit_creds(init_cred) and gain root, i.e. control-flow hijacking and full integrity compromise.\nA:H - Writes to unmapped or critical kernel addresses oops or panic because the original accesses had no exception-table fixups, and corrupting kernel text, data, or the syscall table can hang or crash the machine even without a full root exploit."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/openrisc/kernel/entry.S"],"versions":[{"version":"9d02a4283e9ce4e9ca11ff00615bdacdb0515a1a","lessThan":"bf310718c6fa6adeee06d207a55489546d860e2c","status":"affected","versionType":"git"},{"version":"9d02a4283e9ce4e9ca11ff00615bdacdb0515a1a","lessThan":"497cba0b02e5555d99fe9ee1dc478af743ab7f7a","status":"affected","versionType":"git"},{"version":"9d02a4283e9ce4e9ca11ff00615bdacdb0515a1a","lessThan":"1f2e92e499d863f81df1732af59b4a3559969193","status":"affected","versionType":"git"},{"version":"9d02a4283e9ce4e9ca11ff00615bdacdb0515a1a","lessThan":"574ae2ac2b314aa33498cd2c28add106cbe644f2","status":"affected","versionType":"git"},{"version":"9d02a4283e9ce4e9ca11ff00615bdacdb0515a1a","lessThan":"a520e8cac54fb403f3800125b606f55fcad42cb9","status":"affected","versionType":"git"},{"version":"9d02a4283e9ce4e9ca11ff00615bdacdb0515a1a","lessThan":"d64a75369cd0f2ee79afcc9d9ca34a3890989379","status":"affected","versionType":"git"},{"version":"9d02a4283e9ce4e9ca11ff00615bdacdb0515a1a","lessThan":"b53435c079c78f89f70a62dd5a322cca4e292b34","status":"affected","versionType":"git"},{"version":"9d02a4283e9ce4e9ca11ff00615bdacdb0515a1a","lessThan":"78004e9a87f240df03e2f73120d291763c32e0a7","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/openrisc/kernel/entry.S"],"versions":[{"version":"3.1","status":"affected"},{"version":"0","lessThan":"3.1","status":"unaffected","versionType":"semver"},{"version":"5.10.270","lessThanOrEqual":"5.10.*","status":"unaffected","versionType":"semver"},{"version":"5.15.221","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.1.188","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.157","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.109","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.50","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.2.4","lessThanOrEqual":"7.2.*","status":"unaffected","versionType":"semver"},{"version":"7.3-rc1","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.1","versionEndExcluding":"5.10.270"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.1","versionEndExcluding":"5.15.221"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.1","versionEndExcluding":"6.1.188"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.1","versionEndExcluding":"6.6.157"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.1","versionEndExcluding":"6.12.109"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.1","versionEndExcluding":"6.18.50"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.1","versionEndExcluding":"7.2.4"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.1","versionEndExcluding":"7.3-rc1"}]}]}],"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"}],"title":"openrisc: fix arbitrary kernel memory access via or1k_atomic syscall","x_generator":{"engine":"bippy-1.2.0"}}}}