{"id":"CVE-2026-72114","state":"PUBLISHED","title":"can: bcm: validate frame length in bcm_rx_setup() for RTR replies","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ncan: bcm: validate frame length in bcm_rx_setup() for RTR replies\n\nbcm_tx_setup() validates cf->len against the CAN/CAN FD DLC limits\nbefore installing frames for TX_SETUP, but bcm_rx_setup() never did\nthe same for the RTR-reply frame configured via RX_SETUP with\nRX_RTR_FRAME.","publishedAt":"2026-08-15T05:52:54.750Z","updatedAt":"2026-10-16T18:44:56.572Z","severity":{"score":7.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"ffd980f976e7fd666c2e61bf8ab35107efd11828","status":"affected","lessThan":"cc1f9569f1c1adf74fa69d6f716a31b58a2fc6ce","versionType":"git"},{"version":"ffd980f976e7fd666c2e61bf8ab35107efd11828","status":"affected","lessThan":"204f2b232717bc470ddb9e1da1d27dd9c6ef0caa","versionType":"git"},{"version":"ffd980f976e7fd666c2e61bf8ab35107efd11828","status":"affected","lessThan":"e061624c0a86c3c26a2bf017e432fbc93ad68f3a","versionType":"git"},{"version":"ffd980f976e7fd666c2e61bf8ab35107efd11828","status":"affected","lessThan":"7d966cdee006911d3957e1a4e72cb93c39cd8c1e","versionType":"git"},{"version":"ffd980f976e7fd666c2e61bf8ab35107efd11828","status":"affected","lessThan":"1b475c0c72f44622a320a4386ce9e76f85e69bc7","versionType":"git"},{"version":"ffd980f976e7fd666c2e61bf8ab35107efd11828","status":"affected","lessThan":"deb6a697cce3f021e731df543597f37a5e54caab","versionType":"git"},{"version":"ffd980f976e7fd666c2e61bf8ab35107efd11828","status":"affected","lessThan":"59bfddea64159594feb62ef11b7d7a33c8ee3783","versionType":"git"},{"version":"ffd980f976e7fd666c2e61bf8ab35107efd11828","status":"affected","lessThan":"62ec41f364648be79d54d94d0d240ee326948afd","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/can/bcm.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"2.6.25","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.25","versionType":"semver"},{"version":"5.10.265","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.216","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.183","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.148","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.101","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.42","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.5","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/can/bcm.c"]}],"references":["https://git.kernel.org/stable/c/cc1f9569f1c1adf74fa69d6f716a31b58a2fc6ce","https://git.kernel.org/stable/c/204f2b232717bc470ddb9e1da1d27dd9c6ef0caa","https://git.kernel.org/stable/c/e061624c0a86c3c26a2bf017e432fbc93ad68f3a","https://git.kernel.org/stable/c/7d966cdee006911d3957e1a4e72cb93c39cd8c1e","https://git.kernel.org/stable/c/1b475c0c72f44622a320a4386ce9e76f85e69bc7","https://git.kernel.org/stable/c/deb6a697cce3f021e731df543597f37a5e54caab","https://git.kernel.org/stable/c/59bfddea64159594feb62ef11b7d7a33c8ee3783","https://git.kernel.org/stable/c/62ec41f364648be79d54d94d0d240ee326948afd"],"weaknesses":[],"ingestedAt":"2026-10-29T20:12:58.252Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/72xxx/CVE-2026-72114.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-72114","state":"PUBLISHED","datePublished":"2026-08-15T05:52:54.750Z","dateUpdated":"2026-10-16T18:44:56.572Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-08-09T03:40:39.906Z"},"containers":{"cna":{"title":"can: bcm: validate frame length in bcm_rx_setup() for RTR replies","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ncan: bcm: validate frame length in bcm_rx_setup() for RTR replies\n\nbcm_tx_setup() validates cf->len against the CAN/CAN FD DLC limits\nbefore installing frames for TX_SETUP, but bcm_rx_setup() never did\nthe same for the RTR-reply frame configured via RX_SETUP with\nRX_RTR_FRAME."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"ffd980f976e7fd666c2e61bf8ab35107efd11828","status":"affected","lessThan":"cc1f9569f1c1adf74fa69d6f716a31b58a2fc6ce","versionType":"git"},{"version":"ffd980f976e7fd666c2e61bf8ab35107efd11828","status":"affected","lessThan":"204f2b232717bc470ddb9e1da1d27dd9c6ef0caa","versionType":"git"},{"version":"ffd980f976e7fd666c2e61bf8ab35107efd11828","status":"affected","lessThan":"e061624c0a86c3c26a2bf017e432fbc93ad68f3a","versionType":"git"},{"version":"ffd980f976e7fd666c2e61bf8ab35107efd11828","status":"affected","lessThan":"7d966cdee006911d3957e1a4e72cb93c39cd8c1e","versionType":"git"},{"version":"ffd980f976e7fd666c2e61bf8ab35107efd11828","status":"affected","lessThan":"1b475c0c72f44622a320a4386ce9e76f85e69bc7","versionType":"git"},{"version":"ffd980f976e7fd666c2e61bf8ab35107efd11828","status":"affected","lessThan":"deb6a697cce3f021e731df543597f37a5e54caab","versionType":"git"},{"version":"ffd980f976e7fd666c2e61bf8ab35107efd11828","status":"affected","lessThan":"59bfddea64159594feb62ef11b7d7a33c8ee3783","versionType":"git"},{"version":"ffd980f976e7fd666c2e61bf8ab35107efd11828","status":"affected","lessThan":"62ec41f364648be79d54d94d0d240ee326948afd","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/can/bcm.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"2.6.25","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.25","versionType":"semver"},{"version":"5.10.265","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.216","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.183","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.148","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.101","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.42","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.5","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/can/bcm.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/cc1f9569f1c1adf74fa69d6f716a31b58a2fc6ce"},{"url":"https://git.kernel.org/stable/c/204f2b232717bc470ddb9e1da1d27dd9c6ef0caa"},{"url":"https://git.kernel.org/stable/c/e061624c0a86c3c26a2bf017e432fbc93ad68f3a"},{"url":"https://git.kernel.org/stable/c/7d966cdee006911d3957e1a4e72cb93c39cd8c1e"},{"url":"https://git.kernel.org/stable/c/1b475c0c72f44622a320a4386ce9e76f85e69bc7"},{"url":"https://git.kernel.org/stable/c/deb6a697cce3f021e731df543597f37a5e54caab"},{"url":"https://git.kernel.org/stable/c/59bfddea64159594feb62ef11b7d7a33c8ee3783"},{"url":"https://git.kernel.org/stable/c/62ec41f364648be79d54d94d0d240ee326948afd"}],"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 - The missing validation is in bcm_rx_setup(), reached only via local PF_CAN SOCK_DGRAM CAN_BCM syscalls (socket/connect/sendmsg RX_SETUP with RX_RTR_FRAME); it is not triggered by remote IP services or by CAN bus traffic alone.\nAC:L - An attacker reliably installs a malformed RTR-reply frame with a single RX_SETUP sendmsg and can trigger bcm_can_tx() by sending or waiting for a matching RTR on the bound interface, with no races or layout dependencies beyond their control.\nPR:L - can_create(), bcm_connect(), and bcm_sendmsg() perform no capability checks; any local user with access to a CAN interface (including vcan created with CAP_NET_ADMIN in an unprivileged user namespace) can open BCM sockets and program RX_SETUP RTR replies.\nUI:N - Exploitation requires only the attacker opening a BCM socket and sending RX_SETUP messages; no victim interaction such as mounting filesystems or opening files is needed once local CAN access exists.\nS:U - Impact is kernel memory corruption and unauthorized CAN frame transmission within the same host security domain; it does not cross VM, container, or IOMMU boundaries even when frames reach an adjacent vehicle or industrial CAN segment.\nC:H - Unvalidated cf->len values are stored in op->frames and later passed to bcm_can_tx()/can_send(); many CAN driver ndo_start_xmit paths memcpy(cf->data, cf->len) trusting len, enabling out-of-bounds kernel reads when invalid lengths bypass or race skb validation.\nI:H - Attacker-controlled len in the RTR-reply frame can drive out-of-bounds memcpy writes in CAN USB/SPI/hardware xmit paths and inject attacker-crafted frame payloads onto safety-critical automotive, factory, or embedded CAN buses when RTR requests are answered.\nA:H - Out-of-bounds accesses in CAN driver transmit paths from trusted-but-invalid len values can cause kernel WARN/Oops/panic on hardened builds, and repeated malformed RTR-reply transmission attempts can wedge TX queues or disrupt CAN service on affected 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ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-72114","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"version":"2.0.3","timestamp":"2026-10-16T18:41:46.302799Z"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-16T18:44:56.572Z"}}]}}}