{"id":"DEBIAN-CVE-2023-53246","details":"In the Linux kernel, the following vulnerability has been resolved:  cifs: fix DFS traversal oops without CONFIG_CIFS_DFS_UPCALL  When compiled with CONFIG_CIFS_DFS_UPCALL disabled, cifs_dfs_d_automount is NULL. cifs.ko logic for mapping CIFS_FATTR_DFS_REFERRAL attributes to S_AUTOMOUNT and corresponding dentry flags is retained regardless of CONFIG_CIFS_DFS_UPCALL, leading to a NULL pointer dereference in VFS follow_automount() when traversing a DFS referral link:   BUG: kernel NULL pointer dereference, address: 0000000000000000   ...   Call Trace:    \u003cTASK\u003e    __traverse_mounts+0xb5/0x220    ? cifs_revalidate_mapping+0x65/0xc0 [cifs]    step_into+0x195/0x610    ? lookup_fast+0xe2/0xf0    path_lookupat+0x64/0x140    filename_lookup+0xc2/0x140    ? __create_object+0x299/0x380    ? kmem_cache_alloc+0x119/0x220    ? user_path_at_empty+0x31/0x50    user_path_at_empty+0x31/0x50    __x64_sys_chdir+0x2a/0xd0    ? exit_to_user_mode_prepare+0xca/0x100    do_syscall_64+0x42/0x90    entry_SYSCALL_64_after_hwframe+0x72/0xdc  This fix adds an inline cifs_dfs_d_automount() {return -EREMOTE} handler when CONFIG_CIFS_DFS_UPCALL is disabled. An alternative would be to avoid flagging S_AUTOMOUNT, etc. without CONFIG_CIFS_DFS_UPCALL. This approach was chosen as it provides more control over the error path.","modified":"2026-09-15T09:03:02.626288502Z","published":"2025-09-15T15:15:51.803Z","upstream":["CVE-2023-53246"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2023-53246"}],"affected":[{"package":{"name":"linux","ecosystem":"Debian:12","purl":"pkg:deb/debian/linux?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.1.25-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2023-53246.json"}},{"package":{"name":"linux","ecosystem":"Debian:13","purl":"pkg:deb/debian/linux?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.1.25-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2023-53246.json"}},{"package":{"name":"linux","ecosystem":"Debian:14","purl":"pkg:deb/debian/linux?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.1.25-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2023-53246.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"}]}