{"id":"CVE-2026-64048","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/smc: reject CHID-0 ACCEPT that matches an empty ism_dev slot\n\nOn the SMC-D client, slot 0 of ini->ism_dev[]/ini->ism_chid[] is\nreserved for an SMC-Dv1 device","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/smc: reject CHID-0 ACCEPT that matches an empty ism_dev slot\n\nOn the SMC-D client, slot 0 of ini->ism_dev[]/ini->ism_chid[] is\nreserved for an SMC-Dv1 device. smc_f…","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","published":"2026-07-19","updated":"2026-08-23","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-64048","references":[{"url":"https://git.kernel.org/stable/c/277740023def559a4a2ddc3e8e784ee37a0f16a9","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/53eb7bd09aace72fa17510d80e0caf5ca058c231","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/65edb3b0822cfe5041be8fbabebd57e2e5ad9f4e","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/6927cacf2b10d4fa80c1a2d407512ef9397c59c6","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/903f7688ffeb9b323d70652c01f554bd4ba2a3d6","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/afa9036b8c9963947b487c36e332df6a42c96fcb","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/d38ba387244e5c5f7db3e11ea98bc2c7beccb0c0","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/dd2f9dd83c68abd7ba7ded7075290b016cb7ecd0","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-64048.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-64048"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2502589"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-64048"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64048"},{"url":"https://lore.kernel.org/linux-cve-announce/2026071907-CVE-2026-64048-a8e3@gregkh/T"},{"url":"https://access.redhat.com/errata/RHSA-2026:88477"},{"url":"https://access.redhat.com/errata/RHSA-2026:57252"},{"url":"https://access.redhat.com/errata/RHSA-2026:57253"},{"url":"https://access.redhat.com/errata/RHSA-2026:57254"}],"tags":["nvd","cve.org","csaf","vex","red-hat"],"epss":0.00501,"epssPercentile":0.42713,"ingestedAt":"2026-08-23T13:48:05.294Z","vendor":"Linux","product":"Linux","affected":["Linux >= a7c9c5f4af7f6098da68705fc5d86565d0728ef7 < 903f7688ffeb9b323d70652c01f554bd4ba2a3d6","Linux >= a7c9c5f4af7f6098da68705fc5d86565d0728ef7 < dd2f9dd83c68abd7ba7ded7075290b016cb7ecd0","Linux >= a7c9c5f4af7f6098da68705fc5d86565d0728ef7 < 6927cacf2b10d4fa80c1a2d407512ef9397c59c6","Linux >= a7c9c5f4af7f6098da68705fc5d86565d0728ef7 < d38ba387244e5c5f7db3e11ea98bc2c7beccb0c0","Linux >= a7c9c5f4af7f6098da68705fc5d86565d0728ef7 < 53eb7bd09aace72fa17510d80e0caf5ca058c231","Linux >= a7c9c5f4af7f6098da68705fc5d86565d0728ef7 < afa9036b8c9963947b487c36e332df6a42c96fcb","Linux >= a7c9c5f4af7f6098da68705fc5d86565d0728ef7 < 65edb3b0822cfe5041be8fbabebd57e2e5ad9f4e","Linux >= a7c9c5f4af7f6098da68705fc5d86565d0728ef7 < 277740023def559a4a2ddc3e8e784ee37a0f16a9","Linux 5.10"],"ssvc":{"exploitation":"none","automatable":"yes","technicalImpact":"partial","timestamp":"2026-10-16T15:35:56.958231Z"},"patched":["10base_smtv","enterprise_linux_appstream_v_10","enterprise_linux_appstream_v_9","enterprise_linux_baseos_v_10","enterprise_linux_baseos_v_8","enterprise_linux_baseos_v_9","enterprise_linux_codeready_linux_builder_v_10","enterprise_linux_crb_v_8","enterprise_linux_codeready_linux_builder_v_9","enterprise_linux_hidden_v_10","enterprise_linux_real_time_for_nfv_v_10","enterprise_linux_nfv_v_8","enterprise_linux_real_time_for_nfv_v_9","enterprise_linux_real_time_v_10","enterprise_linux_rt_v_8","enterprise_linux_real_time_v_9"],"cwe":["CWE-476"],"scores":{"nvd":7.5,"vendor":7},"slug":"CVE-2026-64048","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nnet/smc: reject CHID-0 ACCEPT that matches an empty ism_dev slot\n\nOn the SMC-D client, slot 0 of ini->ism_dev[]/ini->ism_chid[] is\nreserved for an SMC-Dv1 device. smc_find_ism_v2_device_clnt()\npopulates V2 entries starting at index 1, so when no V1 device is\nselected slot 0 is left in its kzalloc()'ed state with ism_dev[0] ==\nNULL and ism_chid[0] == 0.\n\nsmc_v2_determine_accepted_chid() then matches the peer's CHID against\nthe array starting from index 0 using the CHID alone. A malicious\npeer replying to a SMC-Dv2-only proposal with d1.chid == 0 matches\nthe empty slot, ini->ism_selected becomes 0, and the subsequent\nism_dev[0]->lgr_lock dereference in smc_conn_create() faults at\noffsetof(struct smcd_dev, lgr_lock) == 0x68:\n\n  BUG: KASAN: null-ptr-deref in _raw_spin_lock_bh+0x79/0xe0\n  Write of size 4 at addr 0000000000000068 by task exploit/144\n  Call Trace:\n   _raw_spin_lock_bh\n   smc_conn_create (net/smc/smc_core.c:1997)\n   __smc_connect (net/smc/af_smc.c:1447)\n   smc_connect (net/smc/af_smc.c:1720)\n   __sys_connect\n   __x64_sys_connect\n   do_syscall_64\n\nRequire ism_dev[i] to be non-NULL before accepting a CHID match.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **RHSA-2026:88477** · Red Hat · fixed in: 10Base-SMTV, Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux BaseOS (v. 10), Red Hat Enterprise Linux CodeReady Linux Builder (v. 10), Red Hat Enterprise Linux Hidden (v. 10), Red Hat Enterprise Linux Real Time for NFV (v. 10), … · released 2026-10-23 · [advisory](https://access.redhat.com/errata/RHSA-2026:88477)\n- **RHSA-2026:57252** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 9), Red Hat Enterprise Linux BaseOS (v. 9), Red Hat Enterprise Linux CodeReady Linux Builder (v. 9), Red Hat Enterprise Linux Real Time for NFV (v. 9), Red Hat Enterprise Linux Real Time (v. 9) · released 2026-08-20 · [advisory](https://access.redhat.com/errata/RHSA-2026:57252)\n- **RHSA-2026:57253** · Red Hat · fixed in: Red Hat Enterprise Linux BaseOS (v. 8), Red Hat Enterprise Linux CRB (v. 8) · released 2026-08-20 · [advisory](https://access.redhat.com/errata/RHSA-2026:57253)\n- **RHSA-2026:57254** · Red Hat · fixed in: Red Hat Enterprise Linux NFV (v. 8), Red Hat Enterprise Linux RT (v. 8) · released 2026-08-20 · [advisory](https://access.redhat.com/errata/RHSA-2026:57254)\n- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 9 · no fix planned: Red Hat Enterprise Linux 9 · updated 2026-10-23 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-64048.json)","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":41.3,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}