{"cve":{"cve_id":"CVE-2026-52944","is_kev":false,"kev_date_added":null,"kev_vendor_project":null,"kev_product":null,"kev_vulnerability_name":null,"kev_short_description":null,"kev_required_action":null,"kev_due_date":null,"kev_known_ransomware":null,"kev_notes":null,"kev_cwes":null,"epss_score":null,"epss_percentile":null,"epss_as_of":null,"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: fix FSCTL permission bypass by adding a permission check for FSCTL_SET_SPARSE\n\nFSCTL_SET_SPARSE in fsctl_set_sparse() modifies the file's sparse\nattribute and saves it through xattr without any permission checks.\n\nThis exposes two issues:\n\n1) A client on a read-only share can change the sparse attribute\n   on files it opened, even though the share is read-only.\n   Other FSCTL write operations already check\n   test_tree_conn_flag(work->tcon, KSMBD_TREE_CONN_FLAG_WRITABLE),\n   but FSCTL_SET_SPARSE does not.\n\n2) Even on writable shares, clients without FILE_WRITE_DATA or\n   FILE_WRITE_ATTRIBUTES access should not modify the sparse\n   attribute. Similar handle-level checks exist in other functions\n   but are missing here.\n\nAdd both share-level writable check and per-handle access check.\nUse goto out on error to avoid leaking file references.","published_at":"2026-06-24T09:59:09.149000Z","last_modified_at":null,"cvss_v3_score":null,"cvss_v3_vector":null,"cvss_v3_severity":null,"cvss_v4_score":null,"cvss_v4_vector":null,"cvss_v4_severity":null,"ssvc_decision":null,"ssvc_exploitation":null,"ssvc_automatable":null,"ssvc_technical_impact":null,"cwes":null,"nvd_references":["https://git.kernel.org/stable/c/3127a884525dc8ca4def73254bfcd3ccef0bf812","https://git.kernel.org/stable/c/de9eb0b44fa9123170e6245b49638e0e453c10f8","https://git.kernel.org/stable/c/aef151bcfa494bfe983669de2726734b534adb73","https://git.kernel.org/stable/c/cc57232cae23c0df91b4a59d0f519141ce9b5b02"],"vuln_status":null,"trending_score":null,"is_trending":false,"has_trended":false,"trended_number_one":false,"trending_peak_score":null,"trending_peak_rank":null,"started_trending_at":null,"trended_number_one_at":null,"summary_generated":null,"summary_generated_at":null,"summary_model":null,"created_at":"2026-06-28T17:55:22.518073Z","updated_at":"2026-06-28T23:30:49.890169Z"},"effective_severity":null,"badges":[],"impact_analysis":[],"cvss_v3_decoded":{"version":null,"metrics":[]},"cvss_v4_decoded":{"version":null,"metrics":[]},"affected":[{"vendor_slug":"linux","vendor_name":"Linux","product_slug":"linux","product_name":"Linux","version_start":"e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9","version_start_inclusive":true,"version_end":"3127a884525dc8ca4def73254bfcd3ccef0bf812","version_end_inclusive":false,"cpe23_uri":"cve5:linux:linux:e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9:3127a884525dc8ca4def73254bfcd3ccef0bf812"},{"vendor_slug":"linux","vendor_name":"Linux","product_slug":"linux","product_name":"Linux","version_start":"e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9","version_start_inclusive":true,"version_end":"de9eb0b44fa9123170e6245b49638e0e453c10f8","version_end_inclusive":false,"cpe23_uri":"cve5:linux:linux:e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9:de9eb0b44fa9123170e6245b49638e0e453c10f8"},{"vendor_slug":"linux","vendor_name":"Linux","product_slug":"linux","product_name":"Linux","version_start":"e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9","version_start_inclusive":true,"version_end":"aef151bcfa494bfe983669de2726734b534adb73","version_end_inclusive":false,"cpe23_uri":"cve5:linux:linux:e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9:aef151bcfa494bfe983669de2726734b534adb73"},{"vendor_slug":"linux","vendor_name":"Linux","product_slug":"linux","product_name":"Linux","version_start":"e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9","version_start_inclusive":true,"version_end":"cc57232cae23c0df91b4a59d0f519141ce9b5b02","version_end_inclusive":false,"cpe23_uri":"cve5:linux:linux:e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9:cc57232cae23c0df91b4a59d0f519141ce9b5b02"},{"vendor_slug":"linux","vendor_name":"Linux","product_slug":"linux","product_name":"Linux","version_start":"5.15","version_start_inclusive":true,"version_end":"5.15","version_end_inclusive":true,"cpe23_uri":"cve5:linux:linux:5.15:5.15"},{"vendor_slug":"linux","vendor_name":"Linux","product_slug":"linux","product_name":"Linux","version_start":"0","version_start_inclusive":true,"version_end":"5.15","version_end_inclusive":false,"cpe23_uri":"cve5:linux:linux:0:5.15"},{"vendor_slug":"linux","vendor_name":"Linux","product_slug":"linux","product_name":"Linux","version_start":"6.6.143","version_start_inclusive":true,"version_end":"6.6.*","version_end_inclusive":true,"cpe23_uri":"cve5:linux:linux:6.6.143:6.6.*"},{"vendor_slug":"linux","vendor_name":"Linux","product_slug":"linux","product_name":"Linux","version_start":"6.18.35","version_start_inclusive":true,"version_end":"6.18.*","version_end_inclusive":true,"cpe23_uri":"cve5:linux:linux:6.18.35:6.18.*"},{"vendor_slug":"linux","vendor_name":"Linux","product_slug":"linux","product_name":"Linux","version_start":"7.0.12","version_start_inclusive":true,"version_end":"7.0.*","version_end_inclusive":true,"cpe23_uri":"cve5:linux:linux:7.0.12:7.0.*"},{"vendor_slug":"linux","vendor_name":"Linux","product_slug":"linux","product_name":"Linux","version_start":"7.1","version_start_inclusive":true,"version_end":"*","version_end_inclusive":true,"cpe23_uri":"cve5:linux:linux:7.1:*"}],"exploit_refs":[],"news":[],"references":[{"url":"https://git.kernel.org/stable/c/3127a884525dc8ca4def73254bfcd3ccef0bf812","source_type":"MISC","tags":[]},{"url":"https://git.kernel.org/stable/c/de9eb0b44fa9123170e6245b49638e0e453c10f8","source_type":"MISC","tags":[]},{"url":"https://git.kernel.org/stable/c/aef151bcfa494bfe983669de2726734b534adb73","source_type":"MISC","tags":[]},{"url":"https://git.kernel.org/stable/c/cc57232cae23c0df91b4a59d0f519141ce9b5b02","source_type":"MISC","tags":[]}],"timeline":[{"type":"published","at":"2026-06-24T09:59:09.149000Z","label":"CVE published","source":null}]}