CVE-2025-21993

HIGH EPSS 8.6%
Published Apr 2, 20251y ago · Modified Jun 17, 20262w ago
7.1 CVSS 3.1
High
Find Similar
Published Apr 2, 2025 1y ago
Last Modified Jun 17, 2026 2w ago

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.

CVSS Details

Base Score
7.1
Exploitability
1.8
Impact
5.2
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
Attack Vector Local
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality High
Integrity None
Availability High

Threat Intelligence

EPSS Exploit Probability
8.6% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 1

CWE-125 Out-of-bounds Read Memory Safety

Affected Products 5

VendorProductVersionRange
linuxlinux_kernel* <6.1.132
linuxlinux_kernel*≥6.2  –  <6.6.84
linuxlinux_kernel*≥6.7  –  <6.12.20
linuxlinux_kernel*≥6.13  –  <6.13.8
linuxlinux_kernel6.14any

References 10

  • git.kernel.org https://git.kernel.org/stable/c/07e0d99a2f701123ad3104c0f1a1e66bce74d6e5
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/2d1eef248107bdf3d5a69d0fde04c30a79a7bf5d
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/9bfa80c8aa4e06dff55a953c3fffbfc68a3a3b1c
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/a858cd58dea06cf85b142673deea8c5d87f11e70
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/b253660fac5e0e9080d2c95e3a029e1898d49afb
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/b388e185bfad32bfed6a97a6817f74ca00a4318f
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/c1c6e527470e5eab0b2d57bd073530fbace39eab
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/f763c82db8166e28f45b7cc4a5398a7859665940
    Patch
  • lists.debian.org https://lists.debian.org/debian-lts-announce/2025/05/msg00030.html
  • lists.debian.org https://lists.debian.org/debian-lts-announce/2025/05/msg00045.html

Remediation

  • git.kernel.org https://git.kernel.org/stable/c/07e0d99a2f701123ad3104c0f1a1e66bce74d6e5
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/2d1eef248107bdf3d5a69d0fde04c30a79a7bf5d
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/9bfa80c8aa4e06dff55a953c3fffbfc68a3a3b1c
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/a858cd58dea06cf85b142673deea8c5d87f11e70
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/b253660fac5e0e9080d2c95e3a029e1898d49afb
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/b388e185bfad32bfed6a97a6817f74ca00a4318f
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/c1c6e527470e5eab0b2d57bd073530fbace39eab
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/f763c82db8166e28f45b7cc4a5398a7859665940
    Patch