{"schema_version":"1.9.0","id":"CVE-2025-40326","published":"2025-12-08T00:46:53.212Z","modified":"2026-08-12T03:51:11.479404513Z","summary":"NFSD: Define actions for the new time_deleg FATTR4 attributes","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nNFSD: Define actions for the new time_deleg FATTR4 attributes\n\nNFSv4 clients won't send legitimate GETATTR requests for these new\nattributes because they are intended to be used only with CB_GETATTR\nand SETATTR. But NFSD has to do something besides crashing if it\never sees a GETATTR request that queries these attributes.\n\nRFC 8881 Section 18.7.3 states:\n\n> The server MUST return a value for each attribute that the client\n> requests if the attribute is supported by the server for the\n> target file system. If the server does not support a particular\n> attribute on the target file system, then it MUST NOT return the\n> attribute value and MUST NOT set the attribute bit in the result\n> bitmap. The server MUST return an error if it supports an\n> attribute on the target but cannot obtain its value. In that case,\n> no attribute values will be returned.\n\nFurther, RFC 9754 Section 5 states:\n\n> These new attributes are invalid to be used with GETATTR, VERIFY,\n> and NVERIFY, and they can only be used with CB_GETATTR and SETATTR\n> by a client holding an appropriate delegation.\n\nThus there does not appear to be a specific server response mandated\nby specification. Taking the guidance that querying these attributes\nvia GETATTR is \"invalid\", NFSD will return nfserr_inval, failing the\nrequest entirely.","affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"51c0d4f7e317d3cb4a3001e502bd8ca2d57f2a4b"},{"fixed":"d8f3f94dc950e7c62c96af432c26745885b0a18a"},{"fixed":"4f76435fd517981f01608678c06ad9718a86ee98"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-40326.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.14.0"},{"fixed":"6.17.8"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-40326.json"}}],"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/4f76435fd517981f01608678c06ad9718a86ee98"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d8f3f94dc950e7c62c96af432c26745885b0a18a"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/40xxx/CVE-2025-40326.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-40326"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/40xxx/CVE-2025-40326.json"},"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}