vulnerability
Red Hat: CVE-2025-21993: kernel: iscsi_ibft: Fix UBSAN shift-out-of-bounds warning in ibft_attr_show_nic() (Multiple Advisories)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 6 | (AV:L/AC:L/Au:S/C:C/I:N/A:C) | Apr 2, 2025 | May 15, 2025 | Mar 27, 2026 |
Severity
6
CVSS
(AV:L/AC:L/Au:S/C:C/I:N/A:C)
Published
Apr 2, 2025
Added
May 15, 2025
Modified
Mar 27, 2026
Description
In the Linux kernel, the following vulnerability has been resolved:
iscsi_ibft: Fix UBSAN shift-out-of-bounds warning in ibft_attr_show_nic()
When performing an iSCSI boot using IPv6, iscsistart still reads the
/sys/firmware/ibft/ethernetX/subnet-mask entry. Since the IPv6 prefix
length is 64, this causes the shift exponent to become negative,
triggering a UBSAN warning. As the concept of a subnet mask does not
apply to IPv6, the value is set to ~0 to suppress the warning message.
Solutions
redhat-upgrade-kernelredhat-upgrade-kernel-rt
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