{"id":"CVE-2026-80548","title":"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 beca…","summary":"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 beca…","severity":"high","cvss":8.8,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","vendor":"Linux","product":"Linux","affected":["Linux >= 4f76617378ee97c557b526cb58d3c61eb0a9c963 < dab6a6627b0b0cce23653e99c7b0bf8c6cfd82e0","Linux >= 4f76617378ee97c557b526cb58d3c61eb0a9c963 < 56d7488533ceac4e986e96e15c9e487a2245bc01","Linux >= 4f76617378ee97c557b526cb58d3c61eb0a9c963 < f72a51810d49411bd8cad0c2df8592320a2fe5cc","Linux >= 4f76617378ee97c557b526cb58d3c61eb0a9c963 < 2ba9efdf9ebedc4e54df4b56aa3b43a65f7967cd","Linux >= 4f76617378ee97c557b526cb58d3c61eb0a9c963 < b6aecea4b2b246f9fbd98a5712daa1193a60818e","Linux >= 4f76617378ee97c557b526cb58d3c61eb0a9c963 < 2a5ac0c0f1f7da33929211a2e41911bf72ee35d8","Linux >= 4f76617378ee97c557b526cb58d3c61eb0a9c963 < 34f4feff3e90bd09308fad0974e97113b23b812a","Linux 5.2"],"published":"2026-08-26","updated":"2026-10-16","sourceUpdated":"2026-10-16T20:17:58.900","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-80548","references":[{"url":"https://git.kernel.org/stable/c/2a5ac0c0f1f7da33929211a2e41911bf72ee35d8","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/2ba9efdf9ebedc4e54df4b56aa3b43a65f7967cd","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/34f4feff3e90bd09308fad0974e97113b23b812a","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/56d7488533ceac4e986e96e15c9e487a2245bc01","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/b6aecea4b2b246f9fbd98a5712daa1193a60818e","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/dab6a6627b0b0cce23653e99c7b0bf8c6cfd82e0","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/f72a51810d49411bd8cad0c2df8592320a2fe5cc","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd","cve.org"],"epss":0.00176,"epssPercentile":0.07049,"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-10-16T19:17:03.411109Z"},"ingestedAt":"2026-10-16T19:46:24.318Z","slug":"CVE-2026-80548","body":"## Overview\n\nIn 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.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":48,"depthScoreParts":{"impact":48.4,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}