{"cve":"CVE-2026-31590","nvd":{"published":"2026-04-24T15:16:36.170","modified":"2026-06-17T10:34:02.540","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: SEV: Drop WARN on large size for KVM_MEMORY_ENCRYPT_REG_REGION\n\nDrop the WARN in sev_pin_memory() on npages overflowing an int, as the\nWARN is comically trivially to trigger from userspace, e.g. by doing:\n\n  struct kvm_enc_region range = {\n          .addr = 0,\n          .size = -1ul,\n  };\n\n  __vm_ioctl(vm, KVM_MEMORY_ENCRYPT_REG_REGION, &range);\n\nNote, the checks in sev_mem_enc_register_region() that presumably exist to\nverify the incoming address+size are completely worthless, as both \"addr\"\nand \"size\" are u64s and SEV is 64-bit only, i.e. they _can't_ be greater\nthan ULONG_MAX.  That wart will be cleaned up in the near future.\n\n\tif (range->addr > ULONG_MAX || range->size > ULONG_MAX)\n\t\treturn -EINVAL;\n\nOpportunistically add a comment to explain why the code calculates the\nnumber of pages the \"hard\" way, e.g. instead of just shifting @ulen.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":[],"references":["https://git.kernel.org/stable/c/1cba4dcd795daf6d257122779fb6a349edf03914","https://git.kernel.org/stable/c/28cc13ca20431b127d42d84ba10898d03e2c8267","https://git.kernel.org/stable/c/6a8e3c82122737529b25ef2a048fbcc569d8c055","https://git.kernel.org/stable/c/8acffeef5ef720c35e513e322ab08e32683f32f2","https://git.kernel.org/stable/c/a703933bcfa5cc76ca10e2048464600e74136099"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:33:09.003606135+00:00"},"epss":{"cve":"CVE-2026-31590","score":0.00125,"percentile":0.02203,"date":"2026-11-01"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}