{"id":"CVE-2026-74713","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nvhost_iotlb: bound map allocation in add_range\n\nvhost_iotlb_add_range_ctx() only retires an old entry when the table\nhas a non-zero limit, has exactly reached that limi…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nvhost_iotlb: bound map allocation in add_range\n\nvhost_iotlb_add_range_ctx() only retires an old entry when the table\nhas a non-zero limit, has exactly reached that limi…","severity":"high","cvss":7.1,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H","published":"2026-08-22","updated":"2026-10-14","sourceUpdated":"2026-10-14T13:10:00.187","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-74713","references":[{"url":"https://git.kernel.org/stable/c/1ed35ac7f3fe2b4396bdd29ac3a7f0ebc0829e94","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/ae128dd19040ee06a4f8143c7ced4d18080d7a9a","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd"],"epss":0.0016,"epssPercentile":0.04728,"ingestedAt":"2026-10-14T13:30:58.545Z","slug":"CVE-2026-74713","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nvhost_iotlb: bound map allocation in add_range\n\nvhost_iotlb_add_range_ctx() only retires an old entry when the table\nhas a non-zero limit, has exactly reached that limit and has\nVHOST_IOTLB_FLAG_RETIRE set. Non-retiring tables can keep allocating\nentries after reaching their configured limit.\n\nExisting vhost devices allocate their IOTLB with max_iotlb_entries from\nvhost.c, which defaults to 2048 and is tunable by module parameter. Use\nthe caller-provided limit at the allocation point instead of adding a\nseparate default in the common IOTLB helper, and reject non-positive\nvalues in vhost paths that can report an error.\n\nOther vhost IOTLB users should not create zero-limit tables when entries\ncan be populated from userspace or guest-controlled requests. Add\ncaller-side max_iotlb_entries parameters for mlx5 vDPA, VDUSE and\nvhost-vDPA. Reject non-positive VDUSE and vhost-vDPA values, and require\nat least two entries for vdpa_sim and mlx5 vDPA paths that install\nfull-range mappings, since those mappings are split into two IOTLB\nentries.\n\nHandle full-range mappings in the common helper by checking that the\nIOTLB can hold both split entries before inserting the first half. This\navoids returning an error after leaving a half mapping behind.\n\nWhen the table is full, keep the existing retire behavior for retiring\ntables and return -ENOSPC for non-retiring tables. Reuse the retired map\nnode instead of freeing it and allocating a replacement, so a stream of\nIOTLB updates cannot keep forcing GFP_ATOMIC allocations after the table\nhas reached its limit. If a zero-limit IOTLB still reaches the common\nhelper, treat it as a configuration error and return -EINVAL.\n\nI found this bug myself, though the patch was written with AI assistance.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":39,"depthScoreParts":{"impact":39.1,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}