{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-72122", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-09T03:40:39.907Z", "datePublished": "2026-08-15T05:53:00.704Z", "dateUpdated": "2026-10-16T18:44:57.450Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-17T05:40:35.588Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncan: bcm: fix lockless bound/ifindex race and silent RX_SETUP failure\n\nbcm_sendmsg() reads bo->ifindex and checks bo->bound before taking\nlock_sock(), while bcm_notify(), bcm_connect() and bcm_release() all\nmutate both fields under that same lock. Because the lockless reads\nand the locked writes are unordered with respect to each other, a\nracing bcm_notify() (device unregister) or bcm_connect() (concurrent\nbind on another thread sharing the socket) can make bcm_sendmsg()\nobserve an inconsistent combination, e.g. a stale bound=1 together\nwith the now-cleared ifindex=0, silently turning a socket bound to a\nspecific CAN interface into one that also matches \"any\" interface.\n\nKeep the lockless bo->bound check purely as a fast-path reject, and\nmove the ifindex read (and a bo->bound re-check) into the locked\nsection, where every writer already serializes. This removes the\npossibility of observing the two fields torn against each other,\nrather than trying to fix it with more READ_ONCE()/WRITE_ONCE() pairs\non two independently updated fields. Annotate the now-purely-lockless\nbo->bound accesses consistently across all its write sites.\n\nAlso fix bcm_rx_setup() silently returning success when the target\ndevice disappears concurrently instead of reporting -ENODEV, so a\nbroken RX op is no longer left registered as if it had succeeded." } ], "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:L", "baseScore": 7.3, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - Exploitation requires local access to a PF_CAN SOCK_DGRAM CAN_BCM socket via sendmsg()/connect() syscalls; the race is in kernel socket state handling, not in remote packet reception or the physical CAN bus itself.\nAC:L - The attacker controls both sides of the race by concurrently calling sendmsg() on one thread while triggering bcm_connect() or NETDEV_UNREGISTER (e.g. ip link del) on another, making the torn bound/ifindex observation reliably triggerable.\nPR:L - No real-root capability is required beyond opening BCM sockets and binding to a CAN interface; unprivileged users with CAN access or CAP_NET_ADMIN via user namespaces can create vcan devices and drive the unregister/connect race.\nUI:N - Exploitation is fully attacker-driven through concurrent syscalls and does not require any victim user action such as mounting filesystems or opening files.\nS:U - The impact is unauthorized access to additional CAN interfaces within the same kernel security domain, not a cross-boundary escape such as VM breakout, sandbox escape, or IOMMU bypass.\nC:H - Racing to observe bound=1 with ifindex=0 causes RX_SETUP to register can_rx_register() on all CAN devices, letting a socket bound to one interface sniff traffic from every other CAN bus on the system including safety-critical vehicle or industrial networks.\nI:H - The same torn state enables TX_SETUP/TX_SEND on arbitrary interfaces via msg_name when per-socket binding would normally block it, allowing injection of attacker-controlled CAN frames onto buses the process was not authorized to transmit on.\nA:L - The concurrent bcm_rx_setup() bug can silently return success without registering a filter when the target device vanishes, degrading CAN monitoring reliability without causing kernel panic, oops, or deadlock." } ] } ], "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": "9e60c586faeaed80d55ab8ce2a4b8e56133bc395", "status": "affected", "versionType": "git" }, { "version": "ffd980f976e7fd666c2e61bf8ab35107efd11828", "lessThan": "ffa80a2af27c97453861a5128e537214a31cd18a", "status": "affected", "versionType": "git" }, { "version": "ffd980f976e7fd666c2e61bf8ab35107efd11828", "lessThan": "6bcc5cd247c2934373bc2a1cdf8bf12321169543", "status": "affected", "versionType": "git" }, { "version": "ffd980f976e7fd666c2e61bf8ab35107efd11828", "lessThan": "0f6f9f95294b4cbb26ba02209e893e3bd91237c3", "status": "affected", "versionType": "git" }, { "version": "ffd980f976e7fd666c2e61bf8ab35107efd11828", "lessThan": "b70f1a15533afeeec5d07f20bec3f3867ab1c7b6", "status": "affected", "versionType": "git" }, { "version": "ffd980f976e7fd666c2e61bf8ab35107efd11828", "lessThan": "35f0ac19efb1a3f6c5e12c00e475a9ec2d9c3a6d", "status": "affected", "versionType": "git" }, { "version": "ffd980f976e7fd666c2e61bf8ab35107efd11828", "lessThan": "b9c6ac6fb4e01b34575816066e5d3890a57b3c86", "status": "affected", "versionType": "git" }, { "version": "ffd980f976e7fd666c2e61bf8ab35107efd11828", "lessThan": "d9b091d9d22fee81ec53fb55d2032951993ceadb", "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": "5.10.261", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.212", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.178", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.145", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.97", "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": "2.6.25", "versionEndExcluding": "5.10.261" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.25", "versionEndExcluding": "5.15.212" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.25", "versionEndExcluding": "6.1.178" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.25", "versionEndExcluding": "6.6.145" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.25", "versionEndExcluding": "6.12.97" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.25", "versionEndExcluding": "6.18.40" }, { "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/9e60c586faeaed80d55ab8ce2a4b8e56133bc395" }, { "url": "https://git.kernel.org/stable/c/ffa80a2af27c97453861a5128e537214a31cd18a" }, { "url": "https://git.kernel.org/stable/c/6bcc5cd247c2934373bc2a1cdf8bf12321169543" }, { "url": "https://git.kernel.org/stable/c/0f6f9f95294b4cbb26ba02209e893e3bd91237c3" }, { "url": "https://git.kernel.org/stable/c/b70f1a15533afeeec5d07f20bec3f3867ab1c7b6" }, { "url": "https://git.kernel.org/stable/c/35f0ac19efb1a3f6c5e12c00e475a9ec2d9c3a6d" }, { "url": "https://git.kernel.org/stable/c/b9c6ac6fb4e01b34575816066e5d3890a57b3c86" }, { "url": "https://git.kernel.org/stable/c/d9b091d9d22fee81ec53fb55d2032951993ceadb" } ], "title": "can: bcm: fix lockless bound/ifindex race and silent RX_SETUP failure", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "metrics": [ { "other": { "type": "ssvc", "content": { "id": "CVE-2026-72122", "role": "CISA Coordinator", "options": [ { "Exploitation": "none" }, { "Automatable": "no" }, { "Technical Impact": "total" } ], "version": "2.0.3", "timestamp": "2026-10-16T18:42:08.458786Z" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-16T18:44:57.450Z" } } ] } }