{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-72113", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-09T03:40:39.906Z", "datePublished": "2026-08-15T05:52:54.001Z", "dateUpdated": "2026-08-19T16:35:58.404Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-19T16:35:58.404Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncan: bcm: add missing device refcount for CAN filter removal\n\nsashiko-bot remarked a problem with a concurrent device unregistration\nin isotp.c which also is present in the bcm.c code. A former fix for raw.c\ncommit c275a176e4b6 (\"can: raw: add missing refcount for memory leak fix\")\nintroduced a netdevice_tracker which solves the issue for bcm.c too.\n\nbcm_release(), bcm_delete_rx_op() and bcm_notifier() relied on\ndev_get_by_index(ifindex) to re-find the device for an rx_op before\nunregistering its filter. If a concurrent NETDEV_UNREGISTER has already\nunlisted the device from the ifindex table, that lookup fails and\ncan_rx_unregister() is silently skipped, leaving a stale CAN filter\npointing at the soon-to-be-freed bcm_op/socket.\n\nHold a netdev_hold()/netdev_put() tracked reference on op->rx_reg_dev\nfrom the moment the rx filter is registered in bcm_rx_setup() until it\nis unregistered in bcm_rx_unreg(), and use that reference directly in\nbcm_release() and bcm_delete_rx_op() instead of re-looking the device\nup by ifindex." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - Exploitation requires local syscalls (socket/sendmsg/close) on PF_CAN/CAN_BCM and concurrent netdev teardown via netlink; the flaw is in local filter cleanup, not remote IP packet handling.\nAC:L - An attacker can reliably win the race by concurrently closing the BCM socket or issuing RX_DELETE while deleting the bound vcan/CAN interface from the same user namespace.\nPR:L - BCM sockets need no special capability, and CAP_NET_ADMIN for creating/deleting vcan interfaces is obtainable by unprivileged users via user namespaces (unshare -Urn).\nUI:N - No victim interaction is required; exploitation is fully attacker-driven through BCM socket setup, concurrent netdev removal, and subsequent CAN traffic to hit the stale filter.\nS:U - Impact is confined to kernel memory corruption and privilege escalation within the same security authority; it does not cross VM, container, or IOMMU boundaries.\nC:H - Stale CAN filters leave a use-after-free on freed bcm_op structures; bcm_rx_handler dereferences attacker-influenced freed memory, enabling arbitrary kernel memory disclosure via heap grooming.\nI:H - The UAF in bcm_rx_handler provides write primitives over freed bcm_op fields (timers, frame buffers, socket pointers), enabling control-flow hijacking and arbitrary kernel code execution.\nA:H - Accessing the freed bcm_op from bcm_rx_handler causes kernel oops/panic; UAF is inherently crash-prone even before full exploitation." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/can/bcm.c" ], "versions": [ { "version": "ffd980f976e7fd666c2e61bf8ab35107efd11828", "lessThan": "bd5232663524e94cc5aad861dca11e3db8e2ab6f", "status": "affected", "versionType": "git" }, { "version": "ffd980f976e7fd666c2e61bf8ab35107efd11828", "lessThan": "ee8b36d0faca08f35b889b6e9aa850695e5b8ba9", "status": "affected", "versionType": "git" }, { "version": "ffd980f976e7fd666c2e61bf8ab35107efd11828", "lessThan": "dcaee869913c7210cd47ed0a8f27349d7bdcdb7b", "status": "affected", "versionType": "git" }, { "version": "ffd980f976e7fd666c2e61bf8ab35107efd11828", "lessThan": "84aa4807816e405c1bf87114fc63e06d244281ef", "status": "affected", "versionType": "git" }, { "version": "ffd980f976e7fd666c2e61bf8ab35107efd11828", "lessThan": "633bda66fbf309f5de5e1ad6defe8e6b1d77a20f", "status": "affected", "versionType": "git" }, { "version": "ffd980f976e7fd666c2e61bf8ab35107efd11828", "lessThan": "b024c21c9066f6957b7d4a8f2037e4b000c5e041", "status": "affected", "versionType": "git" }, { "version": "ffd980f976e7fd666c2e61bf8ab35107efd11828", "lessThan": "04d23061bbf18d5d81022eb21e9d32e99d24468d", "status": "affected", "versionType": "git" }, { "version": "ffd980f976e7fd666c2e61bf8ab35107efd11828", "lessThan": "d59948293ea34b6337ce2b5febab8510de70048c", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/can/bcm.c" ], "versions": [ { "version": "2.6.25", "status": "affected" }, { "version": "0", "lessThan": "2.6.25", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.265", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.216", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.183", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.148", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.101", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.42", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1.5", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.25", "versionEndExcluding": "5.10.265" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.25", "versionEndExcluding": "5.15.216" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.25", "versionEndExcluding": "6.1.183" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.25", "versionEndExcluding": "6.6.148" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.25", "versionEndExcluding": "6.12.101" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.25", "versionEndExcluding": "6.18.42" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.25", "versionEndExcluding": "7.1.5" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.25", "versionEndExcluding": "7.2" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/bd5232663524e94cc5aad861dca11e3db8e2ab6f" }, { "url": "https://git.kernel.org/stable/c/ee8b36d0faca08f35b889b6e9aa850695e5b8ba9" }, { "url": "https://git.kernel.org/stable/c/dcaee869913c7210cd47ed0a8f27349d7bdcdb7b" }, { "url": "https://git.kernel.org/stable/c/84aa4807816e405c1bf87114fc63e06d244281ef" }, { "url": "https://git.kernel.org/stable/c/633bda66fbf309f5de5e1ad6defe8e6b1d77a20f" }, { "url": "https://git.kernel.org/stable/c/b024c21c9066f6957b7d4a8f2037e4b000c5e041" }, { "url": "https://git.kernel.org/stable/c/04d23061bbf18d5d81022eb21e9d32e99d24468d" }, { "url": "https://git.kernel.org/stable/c/d59948293ea34b6337ce2b5febab8510de70048c" } ], "title": "can: bcm: add missing device refcount for CAN filter removal", 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