Vulnerabilities > CVE-2025-21993 - Out-of-bounds Read vulnerability in Linux Kernel
Attack vector
LOCAL Attack complexity
LOW Privileges required
LOW Confidentiality impact
HIGH Integrity impact
NONE Availability impact
HIGH Summary
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.
Vulnerable Configurations
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- Overread Buffers An adversary attacks a target by providing input that causes an application to read beyond the boundary of a defined buffer. This typically occurs when a value influencing where to start or stop reading is set to reflect positions outside of the valid memory location of the buffer. This type of attack may result in exposure of sensitive information, a system crash, or arbitrary code execution.
References
- https://git.kernel.org/stable/c/07e0d99a2f701123ad3104c0f1a1e66bce74d6e5
- https://git.kernel.org/stable/c/2d1eef248107bdf3d5a69d0fde04c30a79a7bf5d
- https://git.kernel.org/stable/c/9bfa80c8aa4e06dff55a953c3fffbfc68a3a3b1c
- https://git.kernel.org/stable/c/a858cd58dea06cf85b142673deea8c5d87f11e70
- https://git.kernel.org/stable/c/b253660fac5e0e9080d2c95e3a029e1898d49afb
- https://git.kernel.org/stable/c/b388e185bfad32bfed6a97a6817f74ca00a4318f
- https://git.kernel.org/stable/c/c1c6e527470e5eab0b2d57bd073530fbace39eab
- https://git.kernel.org/stable/c/f763c82db8166e28f45b7cc4a5398a7859665940