Linux KernelOperating system · Linux

CVE-2025-38628

MEDIUM · 5.5 CVSS v3.1 Published 2025-08-22
Fix available
A fix is available. Upgrade to 6.12.42 / 6.15.10 or later.
See remediation →
57/100
Remediation priority · Elevated
Zero-click Patch available

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: vdpa/mlx5: Fix release of uninitialized resources on error path The commit in the fixes tag made sure that mlx5_vdpa_free() is the single entrypoint for removing the vdpa device resources added in mlx5_vdpa_dev_add(), even in the cleanup path of mlx5_vdpa_dev_add(). This means that all functions from mlx5_vdpa_free() should be able to handle uninitialized resources. This was not the case though: mlx5_vdpa_destroy_mr_resources() and mlx5_cmd_cleanup_async_ctx() were not able to do so. This caused the splat below when adding a vdpa device without a MAC address. This patch fixes these remaining issues: - Makes mlx5_vdpa_destroy_mr_resources() return early if called on uninitialized resources. - Moves mlx5_cmd_init_async_ctx() early on during device addition because it can't fail. This means that mlx5_cmd_cleanup_async_ctx() also can't fail. To mirror this, move the call site of mlx5_cmd_cleanup_async_ctx() in mlx5_vdpa_free(). An additional comment was added in mlx5_vdpa_free() to document the expectations of functions called from this context. Splat: mlx5_core 0000:b5:03.2: mlx5_vdpa_dev_add:3950:(pid 2306) warning: No mac address provisioned? ------------[ cut here ]------------ WARNING: CPU: 13 PID: 2306 at kernel/workqueue.c:4207 __flush_work+0x9a/0xb0 [...] Call Trace: <TASK> ? __try_to_del_timer_sync+0x61/0x90 ? __timer_delete_sync+0x2b/0x40 mlx5_vdpa_destroy_mr_resources+0x1c/0x40 [mlx5_vdpa] mlx5_vdpa_free+0x45/0x160 [mlx5_vdpa] vdpa_release_dev+0x1e/0x50 [vdpa] device_release+0x31/0x90 kobject_cleanup+0x37/0x130 mlx5_vdpa_dev_add+0x327/0x890 [mlx5_vdpa] vdpa_nl_cmd_dev_add_set_doit+0x2c1/0x4d0 [vdpa] genl_family_rcv_msg_doit+0xd8/0x130 genl_family_rcv_msg+0x14b/0x220 ? __pfx_vdpa_nl_cmd_dev_add_set_doit+0x10/0x10 [vdpa] genl_rcv_msg+0x47/0xa0 ? __pfx_genl_rcv_msg+0x10/0x10 netlink_rcv_skb+0x53/0x100 genl_rcv+0x24/0x40 netlink_unicast+0x27b/0x3b0 netlink_sendmsg+0x1f7/0x430 __sys_sendto+0x1fa/0x210 ? ___pte_offset_map+0x17/0x160 ? next_uptodate_folio+0x85/0x2b0 ? percpu_counter_add_batch+0x51/0x90 ? filemap_map_pages+0x515/0x660 __x64_sys_sendto+0x20/0x30 do_syscall_64+0x7b/0x2c0 ? do_read_fault+0x108/0x220 ? do_pte_missing+0x14a/0x3e0 ? __handle_mm_fault+0x321/0x730 ? count_memcg_events+0x13f/0x180 ? handle_mm_fault+0x1fb/0x2d0 ? do_user_addr_fault+0x20c/0x700 ? syscall_exit_work+0x104/0x140 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f0c25b0feca [...] ---[ end trace 0000000000000000 ]---

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
How this class of weakness works · CWE-908

Memory or a resource is used before it has been initialised, so its contents are whatever happened to be there — sometimes leaking earlier data, sometimes values an attacker can influence. Behaviour becomes unpredictable and occasionally exploitable. Remediation is initialising every resource before use and ensuring initialisation happens on all code paths.

General guidance for the use of uninitialized resource class — the official description and references above are authoritative for this specific CVE. Want a bespoke review and a reviewed fix? Ask our team →

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Linux KernelOperating system
Affected:>= 6.12.1, < 6.12.42>= 6.13, < 6.15.10>= 6.16, < 6.16.1= 6.12

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
Local
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/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
Upgrade available Upgrade to 6.12.42 / 6.15.10 / 6.16.1 or later
Fixed in 6.12.426.15.106.16.1
Vendor patch git.kernel.org →
Recommended fix High confidence

6.12.42 (or any later fixed version: 6.15.10+, 6.16.1+)

  1. Upgrade the Linux kernel to version 6.12.42 or later to resolve the uninitialized resource issue in the mlx5_vdpa driver.
  2. Alternatively, upgrade to version 6.15.10 or later.
  3. Alternatively, upgrade to version 6.16.1 or later.
Caveat Kernel upgrades may require matching driver versions; ensure mlx5 drivers are compatible with the new kernel version

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

We can perform the upgrade in your staging environment and verify nothing breaks — typical engagement from $1,600. Get the upgrade done

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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-2025-38628 in production — separate from our analysis above.

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