CVE-2026-45973: linux
Vulnerability summary
CVE-2026-45973 is a medium (CVSS 5.5) vulnerability in linux. EPSS estimates a 0.16% chance of exploitation in the next 30 days, higher than 5% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 24 · Related 24Timeline
- 27-05-2026PublishedVulnerability first disclosed.
- 21-10-2026Last modifiedVulnerability information updated.
Description
In the Linux kernel, the following vulnerability has been resolved: RDMA/mlx5: Fix UMR hang in LAG error state unload During firmware reset in LAG mode, a race condition causes the driver to hang indefinitely while waiting for UMR completion during device unload. See [1]. In LAG mode the bond device is only registered on the master, so it never sees sys_error events from the slave. During firmware reset this causes UMR waits to hang forever on unload as the slave is dead but the master hasn't entered error state yet, so UMR posts succeed but completions never arrive. Fix this by adding a sys_error notifier that gets registered before MLX5_IB_STAGE_IB_REG and stays alive until after ib_unregister_device(). This ensures error events reach the bond device throughout teardown. [1] Call Trace: __schedule+0x2bd/0x760 schedule+0x37/0xa0 schedule_preempt_disabled+0xa/0x10 __mutex_lock.isra.6+0x2b5/0x4a0 __mlx5_ib_dereg_mr+0x606/0x870 [mlx5_ib] ? __xa_erase+0x4a/0xa0 ? _cond_resched+0x15/0x30 ? wait_for_completion+0x31/0x100 ib_dereg_mr_user+0x48/0xc0 [ib_core] ? rdmacg_uncharge_hierarchy+0xa0/0x100 destroy_hw_idr_uobject+0x20/0x50 [ib_uverbs] uverbs_destroy_uobject+0x37/0x150 [ib_uverbs] __uverbs_cleanup_ufile+0xda/0x140 [ib_uverbs] uverbs_destroy_ufile_hw+0x3a/0xf0 [ib_uverbs] ib_uverbs_remove_one+0xc3/0x140 [ib_uverbs] remove_client_context+0x8b/0xd0 [ib_core] disable_device+0x8c/0x130 [ib_core] __ib_unregister_device+0x10d/0x180 [ib_core] ib_unregister_device+0x21/0x30 [ib_core] __mlx5_ib_remove+0x1e4/0x1f0 [mlx5_ib] auxiliary_bus_remove+0x1e/0x30 device_release_driver_internal+0x103/0x1f0 bus_remove_device+0xf7/0x170 device_del+0x181/0x410 mlx5_rescan_drivers_locked.part.10+0xa9/0x1d0 [mlx5_core] mlx5_disable_lag+0x253/0x260 [mlx5_core] mlx5_lag_disable_change+0x89/0xc0 [mlx5_core] mlx5_eswitch_disable+0x67/0xa0 [mlx5_core] mlx5_unload+0x15/0xd0 [mlx5_core] mlx5_unload_one+0x71/0xc0 [mlx5_core] mlx5_sync_reset_reload_work+0x83/0x100 [mlx5_core] process_one_work+0x1a7/0x360 worker_thread+0x30/0x390 ? create_worker+0x1a0/0x1a0 kthread+0x116/0x130 ? kthread_flush_work_fn+0x10/0x10 ret_from_fork+0x22/0x40
CVSS metrics
3 scores · 3 sources · 1 version- OSV · UbuntuEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
0.16%
Chance of exploitation in the next 30 days
Percentile
5%
Versus all other CVEs
30-day change
0.00 pp
From 0.16% on 21-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeNo weakness data has been published for this record.
Affected systems
Ubuntu130 products
- linux< 6.8.0-134.134 | All versions (No fix recorded)
- linux-allwinner-5.19All versions (No fix recorded)
- linux-aws< 6.8.0-1060.63 | All versions (No fix recorded)
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.11All versions (No fix recorded)
Linux2 products
- linux≥ 921fcf2971a1e8d3b904ba2c2905b96f4ec3d4ad, < 33deba9bf5c34335182342588315f3db7dbc56d3 | ≥ 6b0acf6a94c31efa43fce4edc22413a3390f9c05, < c8fb5c965ac7d0104872a8e4f6451f3bc6328199 | ≥ ede132a5cf559f3ab35a4c28bac4f4a6c20334d8, < 6d838873da9cb97551d42316967cc82bf8f8031b | ≥ ede132a5cf559f3ab35a4c28bac4f4a6c20334d8, < 613f5d4139b6ba801ccd93f9a28943be60d903bc | ≥ ede132a5cf559f3ab35a4c28bac4f4a6c20334d8, < ebc2164a4cd4314503f1a0c8e7aaf76d7e5fa211 | 542bd62b7a7f37182c9ef192c2bd25d118c144e4 | ≥ 6.6.64, < 6.6.160 | ≥ 6.12.2, < 6.12.75 | ≥ 6.11.11, < 6.12 | 6.13
- linux_kernel≥ 6.6.64, < 6.7 | ≥ 6.11.11, < 6.12 | ≥ 6.12.2, < 6.12.75 | ≥ 6.13, < 6.18.14 | ≥ 6.19, < 6.19.4
Debian1 product
- linux< 6.12.85-1 | < 6.18.14-1
3 vendors · 133 products