{"id":"CVE-2026-52941","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-52941","generatedAt":"2026-10-28T09:41:50.303Z","title":"In the Linux kernel, the following vulnerability has been resolved: net/smc: avoid NULL deref of conn->lnk in smc_msg_event tracepoint The smc_msg_event tracepoint class, shared by smc_tx_sendmsg and smc_rx_recvmsg, unconditionally dereferences…","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/smc: avoid NULL deref of conn->lnk in smc_msg_event tracepoint\n\nThe smc_msg_event tracepoint class, shared by smc_tx_sendmsg and\nsmc_rx_recvmsg, unconditionally dereferences smc->conn.lnk:\n\n\t__string(name, smc->conn.lnk->ibname)\n\nconn->lnk is only set for SMC-R; for SMC-D it is NULL. Other code on\nthese paths already handles this (e.g. !conn->lnk in\nSMC_STAT_RMB_TX_SIZE_SMALL()). With the tracepoint enabled, the first\nsendmsg()/recvmsg() on an SMC-D socket crashes:\n\n  Oops: general protection fault, probably for non-canonical address\n  KASAN: null-ptr-deref in range [...]\n  RIP: 0010:strlen+0x1e/0xa0\n  Call Trace:\n   trace_event_raw_event_smc_msg_event (net/smc/smc_tracepoint.h:44)\n   smc_rx_recvmsg (net/smc/smc_rx.c:515)\n   smc_recvmsg (net/smc/af_smc.c:2859)\n   __sys_recvfrom (net/socket.c:2315)\n   __x64_sys_recvfrom (net/socket.c:2326)\n   do_syscall_64\n\nThe faulting address 0x3e0 is offsetof(struct smc_link, ibname),\nconfirming the NULL ->lnk deref. Enabling the tracepoint requires\nroot, but the trigger itself is unprivileged: socket(AF_SMC, ...) has\nno capability check, and SMC-D negotiation needs no admin step on\ns390 or on x86 with the loopback ISM device loaded.\n\nLog an empty device name for SMC-D instead of dereferencing NULL.","published":"2026-06-24T08:16:24.000Z","lastModified":"2026-07-08T19:10:24.000Z","status":"Analyzed","sourceIdentifier":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","cvss":{"version":"3.1","score":5.5,"severity":"MEDIUM","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"},"cwe":["CWE-476"],"affected":["linux/linux kernel"],"epss":{"score":0.00119,"percentile":0.01752,"date":"2026-10-27","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.12%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"url":"https://git.kernel.org/stable/c/561cf66fa9b6c86dfe4e687d2d1aeaaa6739917f","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/68200112534bb2acd1d7117dc2d5c124868d866d","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/720c76b930c52cd58f50eb6b10569d03dccc7959","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/7bf563badd37cb796df5477d2b78bb64148a1268","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/b706d6d76a2a2793fe5ad0fbc2a75b6a460094ef","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/d2ea0b8aef8746e147602eac87ca8538f4bc7e66","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-52941","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}