{"cve":"CVE-2026-64004","nvd":{"published":"2026-07-19T16:17:40.043","modified":"2026-10-19T21:17:18.343","status":"Modified","description":"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\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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8},"cwes":["CWE-667","CWE-362"],"references":["https://git.kernel.org/stable/c/1fc30bd4e55e2dd622d2d366cecd732c1841bbee","https://git.kernel.org/stable/c/3589d20a666caf30ad100c960a2de7de390fce88","https://git.kernel.org/stable/c/45bb8de8c95d8899f4b8f61bd9bceb8132af73cb","https://git.kernel.org/stable/c/69554adc7a6fa04ede3ad7512321d83748e3c920","https://git.kernel.org/stable/c/6e792b8dd3002bbc4136745928a9605df1a72b8a"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-21T03:43:09.190223697+00:00"},"epss":{"cve":"CVE-2026-64004","score":0.001,"percentile":0.00846,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}