{"cve":"CVE-2026-31717","nvd":{"published":"2026-05-01T14:16:21.860","modified":"2026-06-17T10:34:18.033","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: validate owner of durable handle on reconnect\n\nCurrently, ksmbd does not verify if the user attempting to reconnect\nto a durable handle is the same user who originally opened the file.\nThis allows any authenticated user to hijack an orphaned durable handle\nby predicting or brute-forcing the persistent ID.\n\nAccording to MS-SMB2, the server MUST verify that the SecurityContext\nof the reconnect request matches the SecurityContext associated with\nthe existing open.\nAdd a durable_owner structure to ksmbd_file to store the original opener's\nUID, GID, and account name. and catpure the owner information when a file\nhandle becomes orphaned. and implementing ksmbd_vfs_compare_durable_owner()\nto validate the identity of the requester during SMB2_CREATE (DHnC).","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":8.8},"cwes":[],"references":["https://git.kernel.org/stable/c/00ce8d6789dae72d042a4522264964c72891ca37","https://git.kernel.org/stable/c/49110a8ce654bbe56bef7c5e44cce31f4b102b8a","https://git.kernel.org/stable/c/712cdf917e77a6444ce3836874829d770db20ee6","https://git.kernel.org/stable/c/c7f0f0d01c88bdcb8b1694d7d321670013f7ed7d","https://git.kernel.org/stable/c/c908c853f304a4969b5aa10eba0b50350cc65b80"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:33:09.003606135+00:00"},"epss":{"cve":"CVE-2026-31717","score":0.00437,"percentile":0.38021,"date":"2026-10-31"},"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."]}