CVE-2025-68800
mlxsw: spectrum_mr: Fix use-after-free when updating multicast route stats
Description
In the Linux kernel, the following vulnerability has been resolved: mlxsw: spectrum_mr: Fix use-after-free when updating multicast route stats Cited commit added a dedicated mutex (instead of RTNL) to protect the multicast route list, so that it will not change while the driver periodically traverses it in order to update the kernel about multicast route stats that were queried from the device. One instance of list entry deletion (during route replace) was missed and it can result in a use-after-free [1]. Fix by acquiring the mutex before deleting the entry from the list and releasing it afterwards. [1] BUG: KASAN: slab-use-after-free in mlxsw_sp_mr_stats_update+0x4a5/0x540 drivers/net/ethernet/mellanox/mlxsw/spectrum_mr.c:1006 [mlxsw_spectrum] Read of size 8 at addr ffff8881523c2fa8 by task kworker/2:5/22043 CPU: 2 UID: 0 PID: 22043 Comm: kworker/2:5 Not tainted 6.18.0-rc1-custom-g1a3d6d7cd014 #1 PREEMPT(full) Hardware name: Mellanox Technologies Ltd. MSN2010/SA002610, BIOS 5.6.5 08/24/2017 Workqueue: mlxsw_core mlxsw_sp_mr_stats_update [mlxsw_spectrum] Call Trace: <TASK> dump_stack_lvl+0xba/0x110 print_report+0x174/0x4f5 kasan_report+0xdf/0x110 mlxsw_sp_mr_stats_update+0x4a5/0x540 drivers/net/ethernet/mellanox/mlxsw/spectrum_mr.c:1006 [mlxsw_spectrum] process_one_work+0x9cc/0x18e0 worker_thread+0x5df/0xe40 kthread+0x3b8/0x730 ret_from_fork+0x3e9/0x560 ret_from_fork_asm+0x1a/0x30 </TASK> Allocated by task 29933: kasan_save_stack+0x30/0x50 kasan_save_track+0x14/0x30 __kasan_kmalloc+0x8f/0xa0 mlxsw_sp_mr_route_add+0xd8/0x4770 [mlxsw_spectrum] mlxsw_sp_router_fibmr_event_work+0x371/0xad0 drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c:7965 [mlxsw_spectrum] process_one_work+0x9cc/0x18e0 worker_thread+0x5df/0xe40 kthread+0x3b8/0x730 ret_from_fork+0x3e9/0x560 ret_from_fork_asm+0x1a/0x30 Freed by task 29933: kasan_save_stack+0x30/0x50 kasan_save_track+0x14/0x30 __kasan_save_free_info+0x3b/0x70 __kasan_slab_free+0x43/0x70 kfree+0x14e/0x700 mlxsw_sp_mr_route_add+0x2dea/0x4770 drivers/net/ethernet/mellanox/mlxsw/spectrum_mr.c:444 [mlxsw_spectrum] mlxsw_sp_router_fibmr_event_work+0x371/0xad0 drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c:7965 [mlxsw_spectrum] process_one_work+0x9cc/0x18e0 worker_thread+0x5df/0xe40 kthread+0x3b8/0x730 ret_from_fork+0x3e9/0x560 ret_from_fork_asm+0x1a/0x30
INFO
Published Date :
Jan. 13, 2026, 4:16 p.m.
Last Modified :
Jan. 13, 2026, 4:16 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Solution
- Acquire mutex before deleting list entry.
- Release mutex after deleting list entry.
- Update kernel code with the mutex fix.
- Test the fix in your environment.
References to Advisories, Solutions, and Tools
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information, practical solutions, and valuable tools related to
CVE-2025-68800.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2025-68800 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2025-68800
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
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The following list is the news that have been mention
CVE-2025-68800 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2025-68800 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Jan. 13, 2026
Action Type Old Value New Value Added Description In the Linux kernel, the following vulnerability has been resolved: mlxsw: spectrum_mr: Fix use-after-free when updating multicast route stats Cited commit added a dedicated mutex (instead of RTNL) to protect the multicast route list, so that it will not change while the driver periodically traverses it in order to update the kernel about multicast route stats that were queried from the device. One instance of list entry deletion (during route replace) was missed and it can result in a use-after-free [1]. Fix by acquiring the mutex before deleting the entry from the list and releasing it afterwards. [1] BUG: KASAN: slab-use-after-free in mlxsw_sp_mr_stats_update+0x4a5/0x540 drivers/net/ethernet/mellanox/mlxsw/spectrum_mr.c:1006 [mlxsw_spectrum] Read of size 8 at addr ffff8881523c2fa8 by task kworker/2:5/22043 CPU: 2 UID: 0 PID: 22043 Comm: kworker/2:5 Not tainted 6.18.0-rc1-custom-g1a3d6d7cd014 #1 PREEMPT(full) Hardware name: Mellanox Technologies Ltd. MSN2010/SA002610, BIOS 5.6.5 08/24/2017 Workqueue: mlxsw_core mlxsw_sp_mr_stats_update [mlxsw_spectrum] Call Trace: <TASK> dump_stack_lvl+0xba/0x110 print_report+0x174/0x4f5 kasan_report+0xdf/0x110 mlxsw_sp_mr_stats_update+0x4a5/0x540 drivers/net/ethernet/mellanox/mlxsw/spectrum_mr.c:1006 [mlxsw_spectrum] process_one_work+0x9cc/0x18e0 worker_thread+0x5df/0xe40 kthread+0x3b8/0x730 ret_from_fork+0x3e9/0x560 ret_from_fork_asm+0x1a/0x30 </TASK> Allocated by task 29933: kasan_save_stack+0x30/0x50 kasan_save_track+0x14/0x30 __kasan_kmalloc+0x8f/0xa0 mlxsw_sp_mr_route_add+0xd8/0x4770 [mlxsw_spectrum] mlxsw_sp_router_fibmr_event_work+0x371/0xad0 drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c:7965 [mlxsw_spectrum] process_one_work+0x9cc/0x18e0 worker_thread+0x5df/0xe40 kthread+0x3b8/0x730 ret_from_fork+0x3e9/0x560 ret_from_fork_asm+0x1a/0x30 Freed by task 29933: kasan_save_stack+0x30/0x50 kasan_save_track+0x14/0x30 __kasan_save_free_info+0x3b/0x70 __kasan_slab_free+0x43/0x70 kfree+0x14e/0x700 mlxsw_sp_mr_route_add+0x2dea/0x4770 drivers/net/ethernet/mellanox/mlxsw/spectrum_mr.c:444 [mlxsw_spectrum] mlxsw_sp_router_fibmr_event_work+0x371/0xad0 drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c:7965 [mlxsw_spectrum] process_one_work+0x9cc/0x18e0 worker_thread+0x5df/0xe40 kthread+0x3b8/0x730 ret_from_fork+0x3e9/0x560 ret_from_fork_asm+0x1a/0x30 Added Reference https://git.kernel.org/stable/c/216afc198484fde110ebeafc017992266f4596ce Added Reference https://git.kernel.org/stable/c/37ca08b35a27ce8fd8e74dd3fd2ae21c23b63b73 Added Reference https://git.kernel.org/stable/c/4049a6ace209f4ed150429f86ae796d7d6a4c22b Added Reference https://git.kernel.org/stable/c/5f2831fc593c2b2efbff7dd0dd7441cec76adcd5 Added Reference https://git.kernel.org/stable/c/8ac1dacec458f55f871f7153242ed6ab60373b90