{"id":"CVE-2025-68285","url":"https://www.cyber-defence.io/tools/cve/CVE-2025-68285","generatedAt":"2026-10-28T03:26:27.840Z","title":"In the Linux kernel, the following vulnerability has been resolved: libceph: fix potential use-after-free in have_mon_and_osd_map() The wait loop in __ceph_open_session() can race with the client receiving a new monmap or osdmap shortly after the…","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nlibceph: fix potential use-after-free in have_mon_and_osd_map()\n\nThe wait loop in __ceph_open_session() can race with the client\nreceiving a new monmap or osdmap shortly after the initial map is\nreceived.  Both ceph_monc_handle_map() and handle_one_map() install\na new map immediately after freeing the old one\n\n    kfree(monc->monmap);\n    monc->monmap = monmap;\n\n    ceph_osdmap_destroy(osdc->osdmap);\n    osdc->osdmap = newmap;\n\nunder client->monc.mutex and client->osdc.lock respectively, but\nbecause neither is taken in have_mon_and_osd_map() it's possible for\nclient->monc.monmap->epoch and client->osdc.osdmap->epoch arms in\n\n    client->monc.monmap && client->monc.monmap->epoch &&\n        client->osdc.osdmap && client->osdc.osdmap->epoch;\n\ncondition to dereference an already freed map.  This happens to be\nreproducible with generic/395 and generic/397 with KASAN enabled:\n\n    BUG: KASAN: slab-use-after-free in have_mon_and_osd_map+0x56/0x70\n    Read of size 4 at addr ffff88811012d810 by task mount.ceph/13305\n    CPU: 2 UID: 0 PID: 13305 Comm: mount.ceph Not tainted 6.14.0-rc2-build2+ #1266\n    ...\n    Call Trace:\n    <TASK>\n    have_mon_and_osd_map+0x56/0x70\n    ceph_open_session+0x182/0x290\n    ceph_get_tree+0x333/0x680\n    vfs_get_tree+0x49/0x180\n    do_new_mount+0x1a3/0x2d0\n    path_mount+0x6dd/0x730\n    do_mount+0x99/0xe0\n    __do_sys_mount+0x141/0x180\n    do_syscall_64+0x9f/0x100\n    entry_SYSCALL_64_after_hwframe+0x76/0x7e\n    </TASK>\n\n    Allocated by task 13305:\n    ceph_osdmap_alloc+0x16/0x130\n    ceph_osdc_init+0x27a/0x4c0\n    ceph_create_client+0x153/0x190\n    create_fs_client+0x50/0x2a0\n    ceph_get_tree+0xff/0x680\n    vfs_get_tree+0x49/0x180\n    do_new_mount+0x1a3/0x2d0\n    path_mount+0x6dd/0x730\n    do_mount+0x99/0xe0\n    __do_sys_mount+0x141/0x180\n    do_syscall_64+0x9f/0x100\n    entry_SYSCALL_64_after_hwframe+0x76/0x7e\n\n    Freed by task 9475:\n    kfree+0x212/0x290\n    handle_one_map+0x23c/0x3b0\n    ceph_osdc_handle_map+0x3c9/0x590\n    mon_dispatch+0x655/0x6f0\n    ceph_con_process_message+0xc3/0xe0\n    ceph_con_v1_try_read+0x614/0x760\n    ceph_con_workfn+0x2de/0x650\n    process_one_work+0x486/0x7c0\n    process_scheduled_works+0x73/0x90\n    worker_thread+0x1c8/0x2a0\n    kthread+0x2ec/0x300\n    ret_from_fork+0x24/0x40\n    ret_from_fork_asm+0x1a/0x30\n\nRewrite the wait loop to check the above condition directly with\nclient->monc.mutex and client->osdc.lock taken as appropriate.  While\nat it, improve the timeout handling (previously mount_timeout could be\nexceeded in case wait_event_interruptible_timeout() slept more than\nonce) and access client->auth_err under client->monc.mutex to match\nhow it's set in finish_auth().\n\nmonmap_show() and osdmap_show() now take the respective lock before\naccessing the map as well.","published":"2025-12-16T16:16:07.000Z","lastModified":"2026-10-14T13:10:00.000Z","status":"Deferred","sourceIdentifier":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","cvss":{"version":"3.1","score":9.8,"severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},"cwe":[],"affected":[],"epss":{"score":0.00585,"percentile":0.47693,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.58%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://git.kernel.org/stable/c/05ec43e9a9de67132dc8cd3b22afef001574947f","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/076381c261374c587700b3accf410bdd2dba334e","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/183ad6e3b651e8fb0b66d6a2678f4b80bfbba092","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/3fc43120b22a3d4f1fbeff56a35ce2105b6a5683","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/7c8ccdc1714d9fabecd26e1be7db1771061acc6e","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/bb4910c5fd436701faf367e1b5476a5a6d2aff1c","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/e08021b3b56b2407f37b5fe47b654be80cc665fb","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2025-68285","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}