{"id":"CVE-2026-89559","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-89559","summary":"libnvdimm/labels: Prevent integer overflow in __nd_label_validate()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nlibnvdimm/labels: Prevent integer overflow in __nd_label_validate()\n\nThe on-media namespace index field nslot is a u32 read from the DIMM\nlabel storage area.  __nd_label_validate() bounds it against the config\narea size, but sizeof_namespace_label() returns unsigned, so the product\nnslot * label_size is evaluated in 32-bit and wraps modulo 2^32 before\nthe comparison.  A crafted nslot passes the bound and is then used as the\nloop trip count in nd_label_data_init(), whose memset() walks off the end\nof the config_size buffer: an out-of-bounds write.\n\nThe field is not trusted -- it comes from the medium, or from userspace\nvia ND_CMD_SET_CONFIG_DATA.  Evaluate the product in 64-bit so the bound\ncheck is exact; conforming labels are unaffected.\n\nThe check was safe when introduced by commit 4a826c83db4e (\"libnvdimm:\nnamespace indices: read and validate\"): it multiplied by sizeof(struct\nnd_namespace_label), a size_t, so on a 64-bit build the product did not\nwrap.  Commit 564e871aa66f (\"libnvdimm, label: add v1.2 nvdimm label\ndefinitions\") narrowed it to 32 bits when the label size became a runtime\nvalue read via sizeof_namespace_label().","published":"2026-09-11T19:44:31.337Z","modified":"2026-09-14T03:46:20.390638008Z","cvss":{"score":7.8,"severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[{"ecosystem":"Linux","name":"Kernel","fixedVersion":"6.12.109"}],"fix":null,"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/037770686126155eafc44501312989e2837b9659"},{"type":"WEB","url":"https://git.kernel.org/stable/c/09e649117c54b7e1c004f22eaa19efbadd9ac856"},{"type":"WEB","url":"https://git.kernel.org/stable/c/69a734359639fca16a0dd73ab17a34943e76c68b"},{"type":"WEB","url":"https://git.kernel.org/stable/c/e057efcc9c71d90099d9ee00bed0748d0e9fd586"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89559.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89559"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-09-14T03:46:20.390638008Z"}}