CVE-2026-72113
In the Linux kernel, the following vulnerability has been resolved: can: bcm: add missing device refcount for CAN filter removal sashiko-bot remarked a problem with a concurrent device unregistration in isotp.c which also is present in the bcm.c code.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.16%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
In the Linux kernel, the following vulnerability has been resolved: can: bcm: add missing device refcount for CAN filter removal sashiko-bot remarked a problem with a concurrent device unregistration in isotp.c which also is present in the bcm.c code. A former fix for raw.c commit c275a176e4b6 ("can: raw: add missing refcount for memory leak fix") introduced a netdevice_tracker which solves the issue for bcm.c too. bcm_release(), bcm_delete_rx_op() and bcm_notifier() relied on dev_get_by_index(ifindex) to re-find the device for an rx_op before unregistering its filter. If a concurrent NETDEV_UNREGISTER has already unlisted the device from the ifindex table, that lookup fails and can_rx_unregister() is silently skipped, leaving a stale CAN filter pointing at the soon-to-be-freed bcm_op/socket. Hold a netdev_hold()/netdev_put() tracked reference on op->rx_reg_dev from the moment the rx filter is registered in bcm_rx_setup() until it is unregistered in bcm_rx_unreg(), and use that reference directly in bcm_release() and bcm_delete_rx_op() instead of re-looking the device up by ifindex.
- CVSS 3.1
- 7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 0.16% probability · 6th percentile
- CISA KEV
- Not listed
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/04d23061bbf18d5d81022eb21e9d32e99d24468d
- https://git.kernel.org/stable/c/633bda66fbf309f5de5e1ad6defe8e6b1d77a20f
- https://git.kernel.org/stable/c/84aa4807816e405c1bf87114fc63e06d244281ef
- https://git.kernel.org/stable/c/b024c21c9066f6957b7d4a8f2037e4b000c5e041
- https://git.kernel.org/stable/c/bd5232663524e94cc5aad861dca11e3db8e2ab6f
- https://git.kernel.org/stable/c/d59948293ea34b6337ce2b5febab8510de70048c
- https://git.kernel.org/stable/c/dcaee869913c7210cd47ed0a8f27349d7bdcdb7b
- https://git.kernel.org/stable/c/ee8b36d0faca08f35b889b6e9aa850695e5b8ba9
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.