{"id":"CVE-2025-21993","summary":"iscsi_ibft: Fix UBSAN shift-out-of-bounds warning in ibft_attr_show_nic()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\niscsi_ibft: Fix UBSAN shift-out-of-bounds warning in ibft_attr_show_nic()\n\nWhen performing an iSCSI boot using IPv6, iscsistart still reads the\n/sys/firmware/ibft/ethernetX/subnet-mask entry. Since the IPv6 prefix\nlength is 64, this causes the shift exponent to become negative,\ntriggering a UBSAN warning. As the concept of a subnet mask does not\napply to IPv6, the value is set to ~0 to suppress the warning message.","modified":"2026-04-16T04:35:47.670077128Z","published":"2025-04-02T12:53:15.513Z","related":["ALSA-2025:7423","SUSE-SU-2025:01614-1","SUSE-SU-2025:01707-1","SUSE-SU-2025:01919-1","SUSE-SU-2025:01951-1","SUSE-SU-2025:01964-1","SUSE-SU-2025:01967-1","SUSE-SU-2025:1293-1","SUSE-SU-2025:20192-1","SUSE-SU-2025:20206-1","SUSE-SU-2025:20270-1","SUSE-SU-2025:20283-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/21xxx/CVE-2025-21993.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/07e0d99a2f701123ad3104c0f1a1e66bce74d6e5"},{"type":"WEB","url":"https://git.kernel.org/stable/c/2d1eef248107bdf3d5a69d0fde04c30a79a7bf5d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/9bfa80c8aa4e06dff55a953c3fffbfc68a3a3b1c"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a858cd58dea06cf85b142673deea8c5d87f11e70"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b253660fac5e0e9080d2c95e3a029e1898d49afb"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b388e185bfad32bfed6a97a6817f74ca00a4318f"},{"type":"WEB","url":"https://git.kernel.org/stable/c/c1c6e527470e5eab0b2d57bd073530fbace39eab"},{"type":"WEB","url":"https://git.kernel.org/stable/c/f763c82db8166e28f45b7cc4a5398a7859665940"},{"type":"WEB","url":"https://lists.debian.org/debian-lts-announce/2025/05/msg00030.html"},{"type":"WEB","url":"https://lists.debian.org/debian-lts-announce/2025/05/msg00045.html"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/21xxx/CVE-2025-21993.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-21993"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"138fe4e069798d9aa948a5402ff15e58f483ee4e"},{"fixed":"a858cd58dea06cf85b142673deea8c5d87f11e70"},{"fixed":"f763c82db8166e28f45b7cc4a5398a7859665940"},{"fixed":"b388e185bfad32bfed6a97a6817f74ca00a4318f"},{"fixed":"9bfa80c8aa4e06dff55a953c3fffbfc68a3a3b1c"},{"fixed":"2d1eef248107bdf3d5a69d0fde04c30a79a7bf5d"},{"fixed":"b253660fac5e0e9080d2c95e3a029e1898d49afb"},{"fixed":"c1c6e527470e5eab0b2d57bd073530fbace39eab"},{"fixed":"07e0d99a2f701123ad3104c0f1a1e66bce74d6e5"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-21993.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H"}]}