{"id":"CVE-2025-38003","state":"PUBLISHED","title":"can: bcm: add missing rcu read protection for procfs content","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ncan: bcm: add missing rcu read protection for procfs content\n\nWhen the procfs content is generated for a bcm_op which is in the process\nto be removed the procfs output might show unreliable data (UAF).\n\nAs the removal of bcm_op's is already implemented with rcu handling this\npatch adds the missing rcu_read_lock() and makes sure the list entries\nare properly removed under rcu protection.","publishedAt":"2025-06-08T10:34:55.808Z","updatedAt":"2026-08-05T11:58:54.550Z","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":"5b48f5711f1c630841ab78dcc061de902f0e37bf","status":"affected","lessThan":"19f553a1ddf260da6570ed8f8d91a8c87f49b63a","versionType":"git"},{"version":"85cd41070df992d3c0dfd828866fdd243d3b774a","status":"affected","lessThan":"659701c0b954ccdb4a916a4ad59bbc16e726d42c","versionType":"git"},{"version":"f34f2a18e47b73e48f90a757e1f4aaa8c7d665a1","status":"affected","lessThan":"0622846db728a5332b917c797c733e202c4620ae","versionType":"git"},{"version":"f1b4e32aca0811aa011c76e5d6cf2fa19224b386","status":"affected","lessThan":"6d7d458c41b98a5c1670cbd36f2923c37de51cf5","versionType":"git"},{"version":"f1b4e32aca0811aa011c76e5d6cf2fa19224b386","status":"affected","lessThan":"1f912f8484e9c4396378c39460bbea0af681f319","versionType":"git"},{"version":"f1b4e32aca0811aa011c76e5d6cf2fa19224b386","status":"affected","lessThan":"63567ecd99a24495208dc860d50fb17440043006","versionType":"git"},{"version":"f1b4e32aca0811aa011c76e5d6cf2fa19224b386","status":"affected","lessThan":"7c9db92d5f0eadca30884af75c53d601edc512ee","versionType":"git"},{"version":"f1b4e32aca0811aa011c76e5d6cf2fa19224b386","status":"affected","lessThan":"dac5e6249159ac255dad9781793dbe5908ac9ddb","versionType":"git"},{"version":"fbac09a3b8890003c0c55294c00709f3ae5501bb","status":"affected","versionType":"git"},{"version":"edb4baffb9483141a50fb7f7146cfe4a4c0c2db8","status":"affected","versionType":"git"},{"version":"5.4.205","status":"affected","lessThan":"5.4.294","versionType":"semver"},{"version":"5.10.130","status":"affected","lessThan":"5.10.238","versionType":"semver"},{"version":"5.15.54","status":"affected","lessThan":"5.15.185","versionType":"semver"},{"version":"4.19.252","status":"affected","lessThan":"4.20","versionType":"semver"},{"version":"5.18.11","status":"affected","lessThan":"5.19","versionType":"semver"}],"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":"5.19","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.19","versionType":"semver"},{"version":"5.4.294","status":"unaffected","lessThanOrEqual":"5.4.*","versionType":"semver"},{"version":"5.10.238","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.185","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.141","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.93","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.31","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.14.9","status":"unaffected","lessThanOrEqual":"6.14.*","versionType":"semver"},{"version":"6.15","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/19f553a1ddf260da6570ed8f8d91a8c87f49b63a","https://git.kernel.org/stable/c/659701c0b954ccdb4a916a4ad59bbc16e726d42c","https://git.kernel.org/stable/c/0622846db728a5332b917c797c733e202c4620ae","https://git.kernel.org/stable/c/6d7d458c41b98a5c1670cbd36f2923c37de51cf5","https://git.kernel.org/stable/c/1f912f8484e9c4396378c39460bbea0af681f319","https://git.kernel.org/stable/c/63567ecd99a24495208dc860d50fb17440043006","https://git.kernel.org/stable/c/7c9db92d5f0eadca30884af75c53d601edc512ee","https://git.kernel.org/stable/c/dac5e6249159ac255dad9781793dbe5908ac9ddb","https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html","https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html"],"weaknesses":[],"ingestedAt":"2026-10-29T20:09:09.358Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2025/38xxx/CVE-2025-38003.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2025-38003","state":"PUBLISHED","datePublished":"2025-06-08T10:34:55.808Z","dateUpdated":"2026-08-05T11:58:54.550Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2025-04-16T04:51:23.977Z"},"containers":{"cna":{"title":"can: bcm: add missing rcu read protection for procfs content","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ncan: bcm: add missing rcu read protection for procfs content\n\nWhen the procfs content is generated for a bcm_op which is in the process\nto be removed the procfs output might show unreliable data (UAF).\n\nAs the removal of bcm_op's is already implemented with rcu handling this\npatch adds the missing rcu_read_lock() and makes sure the list entries\nare properly removed under rcu protection."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"5b48f5711f1c630841ab78dcc061de902f0e37bf","status":"affected","lessThan":"19f553a1ddf260da6570ed8f8d91a8c87f49b63a","versionType":"git"},{"version":"85cd41070df992d3c0dfd828866fdd243d3b774a","status":"affected","lessThan":"659701c0b954ccdb4a916a4ad59bbc16e726d42c","versionType":"git"},{"version":"f34f2a18e47b73e48f90a757e1f4aaa8c7d665a1","status":"affected","lessThan":"0622846db728a5332b917c797c733e202c4620ae","versionType":"git"},{"version":"f1b4e32aca0811aa011c76e5d6cf2fa19224b386","status":"affected","lessThan":"6d7d458c41b98a5c1670cbd36f2923c37de51cf5","versionType":"git"},{"version":"f1b4e32aca0811aa011c76e5d6cf2fa19224b386","status":"affected","lessThan":"1f912f8484e9c4396378c39460bbea0af681f319","versionType":"git"},{"version":"f1b4e32aca0811aa011c76e5d6cf2fa19224b386","status":"affected","lessThan":"63567ecd99a24495208dc860d50fb17440043006","versionType":"git"},{"version":"f1b4e32aca0811aa011c76e5d6cf2fa19224b386","status":"affected","lessThan":"7c9db92d5f0eadca30884af75c53d601edc512ee","versionType":"git"},{"version":"f1b4e32aca0811aa011c76e5d6cf2fa19224b386","status":"affected","lessThan":"dac5e6249159ac255dad9781793dbe5908ac9ddb","versionType":"git"},{"version":"fbac09a3b8890003c0c55294c00709f3ae5501bb","status":"affected","versionType":"git"},{"version":"edb4baffb9483141a50fb7f7146cfe4a4c0c2db8","status":"affected","versionType":"git"},{"version":"5.4.205","status":"affected","lessThan":"5.4.294","versionType":"semver"},{"version":"5.10.130","status":"affected","lessThan":"5.10.238","versionType":"semver"},{"version":"5.15.54","status":"affected","lessThan":"5.15.185","versionType":"semver"},{"version":"4.19.252","status":"affected","lessThan":"4.20","versionType":"semver"},{"version":"5.18.11","status":"affected","lessThan":"5.19","versionType":"semver"}],"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":"5.19","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.19","versionType":"semver"},{"version":"5.4.294","status":"unaffected","lessThanOrEqual":"5.4.*","versionType":"semver"},{"version":"5.10.238","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.185","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.141","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.93","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.31","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.14.9","status":"unaffected","lessThanOrEqual":"6.14.*","versionType":"semver"},{"version":"6.15","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/19f553a1ddf260da6570ed8f8d91a8c87f49b63a"},{"url":"https://git.kernel.org/stable/c/659701c0b954ccdb4a916a4ad59bbc16e726d42c"},{"url":"https://git.kernel.org/stable/c/0622846db728a5332b917c797c733e202c4620ae"},{"url":"https://git.kernel.org/stable/c/6d7d458c41b98a5c1670cbd36f2923c37de51cf5"},{"url":"https://git.kernel.org/stable/c/1f912f8484e9c4396378c39460bbea0af681f319"},{"url":"https://git.kernel.org/stable/c/63567ecd99a24495208dc860d50fb17440043006"},{"url":"https://git.kernel.org/stable/c/7c9db92d5f0eadca30884af75c53d601edc512ee"},{"url":"https://git.kernel.org/stable/c/dac5e6249159ac255dad9781793dbe5908ac9ddb"}],"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 a local account to open a PF_CAN/CAN_BCM socket, issue RX_SETUP/RX_DELETE via sendmsg(), and read /proc/net/can-bcm/<inode>. No remote or adjacent network path reaches the racing procfs reader.\nAC:L - The attacker controls both sides of the race entirely — one thread loops reading the procfs entry while another loops RX_SETUP/RX_DELETE — and bcm_proc_show() held no lock whatsoever against the deleter, so the window is hit reliably by simple repetition; a working PoC was produced by the reporter for this bcm series.\nPR:L - can_create() performs no capability check, connect() with ifindex 0 needs no CAN device, and the created proc entry is mode 0644, so any unprivileged local user can drive the whole sequence in its own process (module autoload of can/can-bcm is also unprivileged).\nUI:N - The attacker performs every step itself — socket setup, op deletion, and reading its own procfs file — with no action by any other user.\nS:U - The freed object, the disclosure, and the crash are all within the kernel's own security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - Fields are read from a freed bcm_op and formatted directly into world-readable procfs output; since bcm_op lands in the sprayable kmalloc-512 cache, an attacker reclaiming it controls the list cursor and can steer the walk to arbitrary kernel addresses, leaking their contents to userspace.\nI:H - This is a use-after-free on an attacker-reclaimable slab object whose linkage pointers are dereferenced after free, a primitive that combined with heap grooming is leveraged for kernel state corruption and control-flow influence.\nA:H - A concurrent plain list_del() leaves LIST_POISON1 in the cursor, so the unprotected walker dereferences a non-canonical/freed pointer and oopses; the walk can also spin over reclaimed memory or hit a divide-by-zero on a re-read frames_abs, crashing or hanging the kernel."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-05T11:58:54.550Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.4.205","versionEndExcluding":"5.4.294"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10.130","versionEndExcluding":"5.10.238"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15.54","versionEndExcluding":"5.15.185"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.19","versionEndExcluding":"6.1.141"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.19","versionEndExcluding":"6.6.93"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.19","versionEndExcluding":"6.12.31"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.19","versionEndExcluding":"6.14.9"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.19","versionEndExcluding":"6.15"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.19.252"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.18.11"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CVE Program Container","references":[{"url":"https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html"},{"url":"https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html"}],"providerMetadata":{"shortName":"CVE","orgId":"af854a3a-2127-422b-91ae-364da2661108","dateUpdated":"2025-11-03T17:33:02.902Z"}}]}}}