Linux: Out-of-bounds Read
CVE-2026-53230 is a high-severity out-of-bounds read vulnerability in Linux, with a CVSS 3.1 base score of 8.7 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists versions 87149f3e53f3839454b837f87a2ec7c926775a6a, 41781f2789309462520a93822e946521ed78f97f, 537d87784e81c3d7037525b99416455cee088cdc as the first without the flaw, so updating Linux to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.13% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Linux to 87149f3e53f3839454b837f87a2ec7c926775a6a or 41781f2789309462520a93822e946521ed78f97f or 537d87784e81c3d7037525b99416455cee088cdc or 0f807764bb122fd63aa45f4229cb1ef2679fbd40, whichever matches your release line, or a later version.
- Update Linux Kernel to 6.6.143 or 6.12.94 or 6.18.36 or 7.0.13, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | e16aea2744abea612c27ee0eef606c6a6a8204de up to, but not including, 87149f3e53f3839454b837f87a2ec7c926775a6a; e16aea2744abea612c27ee0eef606c6a6a8204de up to, but not including, 41781f2789309462520a93822e946521ed78f97f; e16aea2744abea612c27ee0eef606c6a6a8204de up to, but not including, 537d87784e81c3d7037525b99416455cee088cdc; e16aea2744abea612c27ee0eef606c6a6a8204de up to, but not including, 0f807764bb122fd63aa45f4229cb1ef2679fbd40; e16aea2744abea612c27ee0eef606c6a6a8204de up to, but not including, 2398e497389ed4be43f7cfbab499b49cec7dae1a; e16aea2744abea612c27ee0eef606c6a6a8204de up to, but not including, 894e036a24a26a6dd7b17d8d3fb5c53ab48a6074; 4.5 | 87149f3e53f3839454b837f87a2ec7c926775a6a, 41781f2789309462520a93822e946521ed78f97f, 537d87784e81c3d7037525b99416455cee088cdc, 0f807764bb122fd63aa45f4229cb1ef2679fbd40, 2398e497389ed4be43f7cfbab499b49cec7dae1a, 894e036a24a26a6dd7b17d8d3fb5c53ab48a6074 |
| Linux | Linux Kernel | 4.5 up to, but not including, 6.6.143; 6.7 up to, but not including, 6.12.94; 6.13 up to, but not including, 6.18.36; 6.19 up to, but not including, 7.0.13; 7.1 | 6.6.143, 6.12.94, 6.18.36, 7.0.13 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- LocalThe attacker needs local access or must trick a user into running something.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Scope
- ChangedThe attack can reach beyond the vulnerable component into other systems.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- LowLimited modification of data is possible.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:H. Scored by CNA.
Official description
In the Linux kernel, the following vulnerability has been resolved: net/mlx5: Fix slab-out-of-bounds in mlx5_query_nic_vport_mac_list mlx5_query_nic_vport_mac_list() sizes its firmware command buffer using the PF's log_max_current_uc/mc_list capabilities. When querying a VF vport with a larger configured max (via devlink), the firmware response can overflow this buffer: BUG: KASAN: slab-out-of-bounds in mlx5_query_nic_vport_mac_list+0x453/0x4c0 [mlx5_core] Read of size 4 at addr ff1100013ffc8a12 by task kworker/u96:2/385 CPU: 12 UID: 0 PID: 385 Comm: kworker/u96:2 Not tainted 7.0.0-rc6+ #1 PREEMPT Hardware name: QEMU Standard PC (Q35 + ICH9, 2009) Workqueue: mlx5_esw_wq esw_vport_change_handler [mlx5_core] Call Trace: <TASK> dump_stack_lvl+0x69/0xa0 print_report+0x176/0x4e4 kasan_report+0xc8/0x100 mlx5_query_nic_vport_mac_list+0x453/0x4c0 [mlx5_core] esw_update_vport_addr_list+0x2e3/0xda0 [mlx5_core] esw_vport_change_handle_locked+0xa1f/0x1060 [mlx5_core] esw_vport_change_handler+0x6a/0x90 [mlx5_core] process_one_work+0x87f/0x15e0 worker_thread+0x62b/0x1020 kthread+0x375/0x490 ret_from_fork+0x4dc/0x810 ret_from_fork_asm+0x11/0x20 </TASK> Fix by querying the vport's own HCA caps to size the buffer correctly. Refactor the function to allocate and return the MAC list internally, removing the caller's dependency on knowing the correct max.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Out-of-bounds Read
The product reads data past the end, or before the beginning, of the intended buffer.
How developers prevent this class of flaw
- Use a language that provides appropriate memory abstractions.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
- git.kernel.org/stable/c/0f807764bb122fd63aa45f4229cb1ef2679fbd40
- git.kernel.org/stable/c/2398e497389ed4be43f7cfbab499b49cec7dae1a
- git.kernel.org/stable/c/41781f2789309462520a93822e946521ed78f97f
- git.kernel.org/stable/c/537d87784e81c3d7037525b99416455cee088cdc
- git.kernel.org/stable/c/894e036a24a26a6dd7b17d8d3fb5c53ab48a6074
Other references
Recent Out-of-bounds Read vulnerabilities
- 7.5 High severity
- 7.1 High severity
- 8.4 High severity
- 9.1 Critical severity
- 8.2 High severity
- 7.1 High severity
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