CVE-2026-49429 - Kernel heap overflow in ZFS_IOC_USERSPACE_MANY ioctl

CVE-2026-49429 - Kernel heap overflow in ZFS_IOC_USERSPACE_MANY ioctl

https://cvefeed.io/rssfeed/latest.atom / Wed, 08/19/2026 - 10:27
CVE ID :CVE-2026-49429
Published : Aug. 19, 2026, 6:17 a.m. | 1 hour, 43 minutes ago
Description :The ZFS_IOC_USERSPACE_MANY ioctl, used by zfs-userspace(8), truncated a 64-bit output buffer size to a 32-bit integer for the kernel allocation, but used the original 64-bit size as the buffer limit when writing records. A local user with the "userused" delegated ZFS permission can trigger a kernel heap overflow via the ZFS_IOC_USERSPACE_MANY ioctl, potentially escalating privileges.
Severity: 0.0 | NA
Visit the link for more details, such as CVSS details, affected products, timeline, and more...

About

Kenya Education Network CERT(KENET-CERT) is a Cybersecurity Emergency Response Team and Co-ordination Center operated by the National Research and Education Network of Kenya. KENET-CERT coordination center promotes awareness on cybersecurity incidences as well as coordinates and assists member institutions in responding effectively to cyber security threats and incidences. KENET-CERT works closely with Kenya's National CIRT coordination center (CIRT/CC) as a sector CIRT for the academic institutions. KENET promotes use of ICT in Teaching, Learning and Research in Higher Education Institutions in Kenya. KENET aims to interconnect all the Universities, Tertiary and Research Institutions in Kenya by setting up a cost effective and sustainable private network with high speed access to the global Internet. KENET also facilitates electronic communication among students and faculties in member institutions, share learning and teaching resources by collaboration in Research and Development of Educational content.