{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-72125", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-09T03:40:39.907Z", "datePublished": "2026-08-15T05:53:02.905Z", "dateUpdated": "2026-08-19T16:36:23.877Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-19T16:36:23.877Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncan: isotp: fix use-after-free race with concurrent NETDEV_UNREGISTER\n\nisotp_release() looked up the bound network device via dev_get_by_index()\nusing the stored ifindex. During device unregistration the device is\nunlisted from the ifindex hash before the NETDEV_UNREGISTER notifier\nchain runs, so a concurrent isotp_release() could find no device, skip\ncan_rx_unregister() entirely, and still proceed to free the socket.\nSince isotp_release() had already removed itself from the isotp\nnotifier list at that point, isotp_notify() would never get a chance to\nclean up either, leaving a stale CAN filter that keeps pointing at the\nfreed socket.\n\nFix this the same way raw.c already does: hold a tracked reference to\nthe bound net_device in the socket (so->dev/so->dev_tracker) from\nbind() onward instead of re-resolving it from the ifindex, and\nserialize bind()/release() with rtnl_lock() so that so->dev is always\nconsistent with what the NETDEV_UNREGISTER notifier sees. so->dev\nstays valid regardless of ifindex-hash unlisting, and is only ever\ncleared by whichever of isotp_release()/isotp_notify() gets there\nfirst, so the filter is always removed exactly once.\n\nisotp_bind() now rejects a (re)bind with -EAGAIN while so->[tx|rx].state\nisn't ISOTP_IDLE yet, so a timer left running by a prior\nNETDEV_UNREGISTER can't act on a newly bound so->ifindex. Both checks\nshare the same lock_sock() section, so there is no window in which a\nconcurrent isotp_notify() clearing so->bound could be missed." } ], "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 AF_CAN ISO-TP socket operations (socket/bind/close) racing NETDEV_UNREGISTER on the bound CAN interface; stale-filter UAF is triggered via local frame injection or an existing bound interface, not a remote IP/network service.\nAC:L - The attacker controls both sides of the race by concurrently closing the ISO-TP socket and unregistering the bound CAN device (e.g., vcan create/delete with CAP_NET_ADMIN in a user namespace), and can retry until the stale RX filter is left on a freed socket.\nPR:L - No init-namespace root is required: any local user can open CAN_ISOTP sockets, and CAP_NET_ADMIN obtainable in user namespaces suffices to create/delete vcan and drive the unregister path used in automotive/embedded ISO-TP (UDS) deployments.\nUI:N - No victim interaction is needed; the use-after-free is triggered by the attacker's own concurrent close()/NETDEV_UNREGISTER operations and subsequent CAN frames sent to the bound IDs.\nS:U - Impact is kernel heap corruption and potential privilege escalation within the same OS security boundary; it does not inherently cross VM, container, or IOMMU isolation boundaries.\nC:H - A stale can_rx filter keeps calling isotp_rcv()/isotp_rcv_echo() with a freed isotp_sock, enabling reads of reallocated slab contents through socket state, sock_queue_rcv_skb(), and protocol parsing on attacker-influenced memory.\nI:H - The UAF path performs extensive writes to freed socket state (RX/TX buffers, timers, generation counters) and can emit CAN traffic, providing primitives for heap shaping and control-flow hijack rather than a crash-only fault.\nA:H - Use-after-free in softirq CAN receive callbacks commonly causes kernel oops/panic from dereferencing or writing freed isotp_sock/timer state, even before reliable exploitation." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/can/isotp.c" ], "versions": [ { "version": "e057dd3fc20ffb3d7f150af46542a51b59b90127", "lessThan": "f311bbb29bb06aaab69ba45a6e4b11323d20b8f9", "status": "affected", "versionType": "git" }, { "version": "e057dd3fc20ffb3d7f150af46542a51b59b90127", "lessThan": "8e018f4335590460ebcf0c2b493ed38ba1a35204", "status": "affected", "versionType": "git" }, { "version": "e057dd3fc20ffb3d7f150af46542a51b59b90127", "lessThan": "33b9cd9245e2a4b800f99ed1cc53d64960614152", "status": "affected", "versionType": "git" }, { "version": "e057dd3fc20ffb3d7f150af46542a51b59b90127", "lessThan": "0b811c4bbe3ec9ad611e90a540fe8b51b3bb8a96", "status": "affected", "versionType": "git" }, { "version": "e057dd3fc20ffb3d7f150af46542a51b59b90127", "lessThan": "43884dc7963beef2328f507f4fe680bdc173eb80", "status": "affected", "versionType": "git" }, { "version": "e057dd3fc20ffb3d7f150af46542a51b59b90127", "lessThan": "7bef39ba76eb7307ed22a50329e0f5776dbeda58", "status": "affected", "versionType": "git" }, { "version": "e057dd3fc20ffb3d7f150af46542a51b59b90127", "lessThan": "e442b62ba5a7756c17e05a77b32cdd085a2b6138", "status": "affected", "versionType": "git" }, { "version": "e057dd3fc20ffb3d7f150af46542a51b59b90127", "lessThan": "20bab8b88baac140ca3701116e1d486c7f51e311", "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/isotp.c" ], "versions": [ { "version": "5.10", "status": "affected" }, { "version": "0", "lessThan": "5.10", "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": "6.18.40", "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": "5.10", "versionEndExcluding": "5.10.265" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.10", "versionEndExcluding": "5.15.216" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.10", "versionEndExcluding": "6.1.183" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.10", "versionEndExcluding": "6.6.148" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.10", "versionEndExcluding": "6.12.101" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.10", "versionEndExcluding": "6.18.40" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.10", "versionEndExcluding": "7.1.5" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.10", "versionEndExcluding": "7.2" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/f311bbb29bb06aaab69ba45a6e4b11323d20b8f9" }, { "url": "https://git.kernel.org/stable/c/8e018f4335590460ebcf0c2b493ed38ba1a35204" }, { "url": "https://git.kernel.org/stable/c/33b9cd9245e2a4b800f99ed1cc53d64960614152" }, { "url": "https://git.kernel.org/stable/c/0b811c4bbe3ec9ad611e90a540fe8b51b3bb8a96" }, { "url": "https://git.kernel.org/stable/c/43884dc7963beef2328f507f4fe680bdc173eb80" }, { "url": "https://git.kernel.org/stable/c/7bef39ba76eb7307ed22a50329e0f5776dbeda58" }, { "url": "https://git.kernel.org/stable/c/e442b62ba5a7756c17e05a77b32cdd085a2b6138" }, { "url": "https://git.kernel.org/stable/c/20bab8b88baac140ca3701116e1d486c7f51e311" } ], "title": "can: isotp: fix use-after-free race with concurrent NETDEV_UNREGISTER", 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