{"id":"CVE-2026-89641","revision":"1f11b8e36f3340c08e715edf4395a7dd","records":[{"revision":"1f11b8e36f3340c08e715edf4395a7dd","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-89641","aliases":[],"title":"cifs: clear tcon after cifsFileInfo_put() in cifs_file_set_size()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ncifs: clear tcon after cifsFileInfo_put() in cifs_file_set_size()\n\nWhen the else branch of cifs_file_set_size() finds a writable file handle\nvia find_writable_file(), it borrows tcon and server from the handle's\ntlink, attempts the handle-based set_file_size() RPC, and then releases\nthe handle with cifsFileInfo_put().\n\nIf set_file_size() fails, execution falls through to the path-based\nfallback, which reuses the borrowed tcon and server under the\n\"if (tcon == NULL)\" guard.  Since tcon is not NULL at that point, the\nguard is skipped.  If cifsFileInfo_put() dropped the last reference on a\ntlink that was already removed from the tlink tree (TCON_LINK_IN_TREE\ncleared, as happens during reconnection or session teardown),\ncifs_put_tlink() will have freed tcon; the subsequent set_path_size()\ncall is then a use-after-free.\n\nSetting tcon = NULL after cifsFileInfo_put() causes the existing guard\nto take the cifs_sb_tlink() path, which acquires a fresh reference for\nthe path-based operation or fails cleanly if the session is gone.","state":0,"publishedAt":"2026-09-11T19:45:34.036+00:00","modifiedAt":"2026-10-19T08:50:13.143+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"fs/smb/client/inode.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"110fee6b9bb58a5c50047fc2594d415f741b591e\",\n                            \"lessThan\": \"4f18c9e7ee464aaae5cd9fccdb943b3fcb4655d4\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"110fee6b9bb58a5c50047fc2594d415f741b591e\",\n                            \"lessThan\": \"4bea15d9c7683218f57b8c1f5f0aa75cab76af8d\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"110fee6b9bb58a5c50047fc2594d415f741b591e\",\n                            \"lessThan\": \"b96db32fed8dfb2478d7c208f89bf383beed1535\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"fs/smb/client/inode.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"6.18\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"6.18\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.50\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2.4\",\n                            \"lessThanOrEqual\": \"7.2.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.3\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8,"severity":"HIGH"}],"references":["https://git.kernel.org/stable/c/4f18c9e7ee464aaae5cd9fccdb943b3fcb4655d4","https://git.kernel.org/stable/c/4bea15d9c7683218f57b8c1f5f0aa75cab76af8d","https://git.kernel.org/stable/c/b96db32fed8dfb2478d7c208f89bf383beed1535"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-89641","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-89641","identifiers":["CVE-2026-89641"]},"retained":false,"historicalAffected":[]}],"coverage":[]}