{"id":"CVE-2026-80548","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-80548","summary":"s390/vfio_ccw: Selectively expand io_mutex","details":"In the Linux kernel, the following vulnerability has been resolved:\n\ns390/vfio_ccw: Selectively expand io_mutex\n\nThe io_mutex was defined to serialize the io_regions, but then has\nalso sort of been associated with the I/O themselves because of\nthe close relationship they share.\n\nWith the handful of races that are possible, the choices are either to:\n A) expand the scope of io_mutex to close these remaining windows, or\n B) reduce the scope of io_mutex to just io_region, and introduce a new\n    lock mechanism for the remaining I/O resources\n\nThis patch implements A, since B brings with it a lot more interactions\nthat would need to be tracked and kept in a correct hierarchy. It also\ntakes advantage of the workqueue element for cp_free() that now gets\ncalled out of fsm_notoper(), which could be invoked out of an interrupt\ncontext and thus cannot acquire a mutex itself.","published":"2026-08-26T14:37:18.759Z","modified":"2026-08-28T03:47:25.886622018Z","cvss":{"score":8.8,"severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H"},"epss":{"score":0.00128,"percentile":0.02782,"asOf":"2026-08-27"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Linux","name":"Kernel","fixedVersion":"5.15.218"}],"fix":null,"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/2a5ac0c0f1f7da33929211a2e41911bf72ee35d8"},{"type":"WEB","url":"https://git.kernel.org/stable/c/2ba9efdf9ebedc4e54df4b56aa3b43a65f7967cd"},{"type":"WEB","url":"https://git.kernel.org/stable/c/34f4feff3e90bd09308fad0974e97113b23b812a"},{"type":"WEB","url":"https://git.kernel.org/stable/c/56d7488533ceac4e986e96e15c9e487a2245bc01"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b6aecea4b2b246f9fbd98a5712daa1193a60818e"},{"type":"WEB","url":"https://git.kernel.org/stable/c/dab6a6627b0b0cce23653e99c7b0bf8c6cfd82e0"},{"type":"WEB","url":"https://git.kernel.org/stable/c/f72a51810d49411bd8cad0c2df8592320a2fe5cc"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/80xxx/CVE-2026-80548.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-80548"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-28T03:47:25.886622018Z"}}