dbcve.org
VulnerabilityAwaiting classification

CVE-2025-68285

CRITICAL · 9.8 CVSS v3.1 Published 2025-12-16
No fix yet
No fix has been published. The vendor has not shipped a fixed release or patch. You remain exposed.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
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 initial map is received. Both ceph_monc_handle_map() and handle_one_map() install a new map immediately after freeing the old one kfree(monc->monmap); monc->monmap = monmap; ceph_osdmap_destroy(osdc->osdmap); osdc->osdmap = newmap; under client->monc.mutex and client->osdc.lock respectively, but because neither is taken in have_mon_and_osd_map() it's possible for client->monc.monmap->epoch and client->osdc.osdmap->epoch arms in client->monc.monmap && client->monc.monmap->epoch && client->osdc.osdmap && client->osdc.osdmap->epoch; condition to dereference an already freed map. This happens to be reproducible with generic/395 and generic/397 with KASAN enabled: BUG: KASAN: slab-use-after-free in have_mon_and_osd_map+0x56/0x70 Read of size 4 at addr ffff88811012d810 by task mount.ceph/13305 CPU: 2 UID: 0 PID: 13305 Comm: mount.ceph Not tainted 6.14.0-rc2-build2+ #1266 ... Call Trace: <TASK> have_mon_and_osd_map+0x56/0x70 ceph_open_session+0x182/0x290 ceph_get_tree+0x333/0x680 vfs_get_tree+0x49/0x180 do_new_mount+0x1a3/0x2d0 path_mount+0x6dd/0x730 do_mount+0x99/0xe0 __do_sys_mount+0x141/0x180 do_syscall_64+0x9f/0x100 entry_SYSCALL_64_after_hwframe+0x76/0x7e </TASK> Allocated by task 13305: ceph_osdmap_alloc+0x16/0x130 ceph_osdc_init+0x27a/0x4c0 ceph_create_client+0x153/0x190 create_fs_client+0x50/0x2a0 ceph_get_tree+0xff/0x680 vfs_get_tree+0x49/0x180 do_new_mount+0x1a3/0x2d0 path_mount+0x6dd/0x730 do_mount+0x99/0xe0 __do_sys_mount+0x141/0x180 do_syscall_64+0x9f/0x100 entry_SYSCALL_64_after_hwframe+0x76/0x7e Freed by task 9475: kfree+0x212/0x290 handle_one_map+0x23c/0x3b0 ceph_osdc_handle_map+0x3c9/0x590 mon_dispatch+0x655/0x6f0 ceph_con_process_message+0xc3/0xe0 ceph_con_v1_try_read+0x614/0x760 ceph_con_workfn+0x2de/0x650 process_one_work+0x486/0x7c0 process_scheduled_works+0x73/0x90 worker_thread+0x1c8/0x2a0 kthread+0x2ec/0x300 ret_from_fork+0x24/0x40 ret_from_fork_asm+0x1a/0x30 Rewrite the wait loop to check the above condition directly with client->monc.mutex and client->osdc.lock taken as appropriate. While at it, improve the timeout handling (previously mount_timeout could be exceeded in case wait_event_interruptible_timeout() slept more than once) and access client->auth_err under client->monc.mutex to match how it's set in finish_auth(). monmap_show() and osdmap_show() now take the respective lock before accessing the map as well.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis

A detailed technical summary for this CVE is being prepared.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Recommended fix High confidence

Upgrade to a kernel version containing the upstream fix commit for this vulnerability (typically merged into stable trees after the mainline commit)

  1. Identify the current kernel version using 'uname -r'
  2. Check if your distribution has released a kernel security update for this CVE
  3. If no vendor update is available, obtain the upstream kernel patch from git.kernel.org (commit related to 'libceph: fix potential use-after-free in have_mon_and_osd_map()')
  4. Apply the patch to the kernel source code, specifically modifying the wait loop in __ceph_open_session() to acquire client->monc.mutex when checking monmap->epoch and client->osdc.lock when checking osdmap->epoch
  5. Rebuild the kernel with the fix applied
  6. Reboot into the fixed kernel
Caveat Kernel recompilation may be required; ensure backup of current kernel and test the new kernel in a non-production environment first

Generated from the published advisory — verify against the referenced sources before acting.

No vendor fix exists The vendor has not published a patch for this.

There is no version to upgrade to and no patch to apply. Every affected install stays exposed until the vendor ships a fix — or somebody else builds one.

Add your voice

Free. We build fixes in the order the community asks for them — and we’ll tell you the moment this one lands.

Can’t wait

We develop and verify an original fix where the vendor hasn’t, from $2,300. Deployed to your staging first — never straight to production.

Scope it with us

See what else the community needs solved on the solutions-needed board.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2025-68285 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2025-68285 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data