{"id":"CVE-2026-49429","state":"PUBLISHED","title":"Kernel heap overflow in ZFS_IOC_USERSPACE_MANY ioctl","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.\n\nA local user with the \"userused\" delegated ZFS permission can trigger a kernel heap overflow via the ZFS_IOC_USERSPACE_MANY ioctl, potentially escalating privileges.","publishedAt":"2026-08-19T05:15:21.198Z","updatedAt":"2026-08-20T03:55:49.215Z","severity":{"score":7.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","source":"CISA-ADP"},"assigner":"freebsd","products":["FreeBSD FreeBSD"],"affected":[{"vendor":"FreeBSD","product":"FreeBSD","defaultStatus":"unknown","versions":[{"version":"15.1-RELEASE","status":"affected","lessThan":"p1","versionType":"release"},{"version":"15.0-RELEASE","status":"affected","lessThan":"p11","versionType":"release"},{"version":"14.4-RELEASE","status":"affected","lessThan":"p7","versionType":"release"},{"version":"14.3-RELEASE","status":"affected","lessThan":"p16","versionType":"release"}],"modules":["zfs"]}],"references":["https://security.freebsd.org/advisories/FreeBSD-SA-26:40.zfs.asc"],"weaknesses":["CWE-122"],"ingestedAt":"2026-10-29T20:12:07.131Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/49xxx/CVE-2026-49429.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-49429","state":"PUBLISHED","datePublished":"2026-08-19T05:15:21.198Z","dateUpdated":"2026-08-20T03:55:49.215Z","assignerShortName":"freebsd","assignerOrgId":"63664ac6-956c-4cba-a5d0-f46076e16109","dateReserved":"2026-05-29T20:24:28.616Z"},"containers":{"cna":{"title":"Kernel heap overflow in ZFS_IOC_USERSPACE_MANY ioctl","descriptions":[{"lang":"en","value":"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.\n\nA local user with the \"userused\" delegated ZFS permission can trigger a kernel heap overflow via the ZFS_IOC_USERSPACE_MANY ioctl, potentially escalating privileges."}],"affected":[{"vendor":"FreeBSD","product":"FreeBSD","defaultStatus":"unknown","versions":[{"version":"15.1-RELEASE","status":"affected","lessThan":"p1","versionType":"release"},{"version":"15.0-RELEASE","status":"affected","lessThan":"p11","versionType":"release"},{"version":"14.4-RELEASE","status":"affected","lessThan":"p7","versionType":"release"},{"version":"14.3-RELEASE","status":"affected","lessThan":"p16","versionType":"release"}],"modules":["zfs"]}],"references":[{"url":"https://security.freebsd.org/advisories/FreeBSD-SA-26:40.zfs.asc","tags":["vendor-advisory"]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-122","description":"CWE-122: Heap-based Buffer Overflow","lang":"en","type":"CWE"}]}],"providerMetadata":{"shortName":"freebsd","orgId":"63664ac6-956c-4cba-a5d0-f46076e16109","dateUpdated":"2026-08-19T05:15:21.198Z"},"datePublic":"2026-06-30T20:00:00.000Z","credits":[{"lang":"en","type":"finder","value":"Yuxiang Yang, Yizhou Zhao, Ao Wang, Xuewei Feng, Qi Li, and Ke Xu from Tsinghua University using GLM-5.1 from Z.ai"},{"lang":"en","type":"finder","value":"Emmanuel Genier at Quarkslab"}],"x_generator":{"engine":"cvelib 1.8.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"cvssV3_1":{"scope":"UNCHANGED","version":"3.1","baseScore":7.8,"attackVector":"LOCAL","baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","integrityImpact":"HIGH","userInteraction":"NONE","attackComplexity":"LOW","availabilityImpact":"HIGH","privilegesRequired":"LOW","confidentialityImpact":"HIGH"}},{"other":{"type":"ssvc","content":{"timestamp":"2026-08-19T00:00:00+00:00","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3","id":"CVE-2026-49429"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-08-20T03:55:49.215Z"}}]}}}