{"id":"CVE-2026-64004","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/iucv: fix locking in .getsockopt\n\nMirror iucv_sock_setsockopt() and wrap the whole switch in\nlock_sock()/release_sock()","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/iucv: fix locking in .getsockopt\n\nMirror iucv_sock_setsockopt() and wrap the whole switch in\nlock_sock()/release_sock(). The pre-existing SO_MSGLIMIT-only lock\nbeco…","severity":"high","cvss":7.8,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-667"],"vendor":"linux","product":"linux_kernel","affected":["linux_kernel >= 3.4, < 5.10.259","linux_kernel >= 5.11, < 5.15.210","linux_kernel >= 5.16, < 6.1.176","linux_kernel >= 6.2, < 6.6.143","linux_kernel >= 6.7, < 6.12.93","linux_kernel >= 6.13, < 6.18.35","linux_kernel >= 6.19, < 7.0.12","linux_kernel = 7.1"],"patched":["linux_kernel 7.0.12"],"published":"2026-07-19","updated":"2026-10-08","sourceUpdated":"2026-10-08T18:37:41.130","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-64004","references":[{"url":"https://git.kernel.org/stable/c/1fc30bd4e55e2dd622d2d366cecd732c1841bbee","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/3589d20a666caf30ad100c960a2de7de390fce88","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/45bb8de8c95d8899f4b8f61bd9bceb8132af73cb","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/69554adc7a6fa04ede3ad7512321d83748e3c920","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/6e792b8dd3002bbc4136745928a9605df1a72b8a","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/884eb247b74d86db97e3a37f0d6fc8e1e83590dd","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/9817369243380e287ebe5525411557eaa3aa2a79","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/cd691beafea0dd779e69e81ccc26b0ab50efcb5e","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd"],"epss":0.00129,"epssPercentile":0.02192,"ingestedAt":"2026-10-08T18:58:11.293Z","slug":"CVE-2026-64004","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nnet/iucv: fix locking in .getsockopt\n\nMirror iucv_sock_setsockopt() and wrap the whole switch in\nlock_sock()/release_sock(). The pre-existing SO_MSGLIMIT-only lock\nbecomes redundant and is removed.\n\nAny AF_IUCV HIPER user can potentially crash the kernel by racing\nrecvmsg() with getsockopt(SO_MSGSIZE): the SO_MSGSIZE arm dereferences\niucv->hs_dev->mtu after iucv_sock_close() (called from the racing\nrecvmsg()) has set hs_dev to NULL, producing a NULL pointer dereference\noops.\n\n## Affected\n\n- `linux_kernel >= 3.4, < 5.10.259`\n- `linux_kernel >= 5.11, < 5.15.210`\n- `linux_kernel >= 5.16, < 6.1.176`\n- `linux_kernel >= 6.2, < 6.6.143`\n- `linux_kernel >= 6.7, < 6.12.93`\n- `linux_kernel >= 6.13, < 6.18.35`\n- `linux_kernel >= 6.19, < 7.0.12`\n- `linux_kernel = 7.1`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `linux_kernel 7.0.12`","depth":"twilight","depthScore":43,"depthScoreParts":{"impact":42.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}