CVE-2025-21993

Aliases:UBUNTU-CVE-2025-21993DEBIAN-CVE-2025-21993
Advisory lineage Upstream: 0 Downstream: 48
Modified
Published: 02 Apr 2025, 12:53
Last modified:11 May 2026, 21:10

Vulnerability Summary

Overall Risk (default)
medium
28/100
CVSS Score
7.1 HIGH
v3.1 (cve.org)
EPSS Score
0.21% LOW
0% probability +0.15%
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

02 Apr 2025, 12:53
Published
Vulnerability first disclosed
11 May 2026, 21:10
Last Modified
Vulnerability information updated

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 Metrics

  • v3.1•HIGH•Score: 7.1CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H

EPSS Trends

Current EPSS score: 0.21%• Percentile: 12%

Techniques & Countermeasures

  • CWE-125•Out-of-bounds Read

    The product reads data past the end, or before the beginning, of the intended buffer.

Affected Systems

  • debian•linux

    < 5.10.237-1 | < 6.1.133-1 | < 6.12.20-1 | < 6.12.20-1

  • debian•linux-6.1

    < 6.1.137-1~deb11u1

  • ubuntu•linux

    all | < 5.4.0-218.238 | < 5.15.0-138.148 | < 6.8.0-58.60

  • ubuntu•linux-allwinner-5.19

    all

  • ubuntu•linux-aws

    all | < 5.4.0-1147.157 | < 5.15.0-1082.89 | < 6.8.0-1027.29

  • ubuntu•linux-aws-5.0

    all

  • ubuntu•linux-aws-5.11

    all

  • ubuntu•linux-aws-5.13

    all

  • ubuntu•linux-aws-5.15

    < 5.15.0-1082.89~20.04.1

  • ubuntu•linux-aws-5.19

    all

  • ubuntu•linux-aws-5.3

    all

  • ubuntu•linux-aws-5.4

    < 5.4.0-1147.157~18.04.1

  • ubuntu•linux-aws-5.8

    all

  • ubuntu•linux-aws-6.2

    all

  • ubuntu•linux-aws-6.5

    all

  • ubuntu•linux-aws-6.8

    < 6.8.0-1027.29~22.04.1

  • ubuntu•linux-aws-fips

    all | < 5.4.0-1147.157+fips1 | < 5.15.0-1082.89+fips1

  • ubuntu•linux-aws-hwe

    all

  • ubuntu•linux-azure

    all | all | < 5.4.0-1152.159 | < 5.15.0-1087.96 | < 6.8.0-1027.32

  • ubuntu•linux-azure-4.15

    all

  • ubuntu•linux-azure-5.11

    all

  • ubuntu•linux-azure-5.13

    all

  • ubuntu•linux-azure-5.15

    < 5.15.0-1087.96~20.04.1

  • ubuntu•linux-azure-5.19

    all

  • ubuntu•linux-azure-5.3

    all

  • ubuntu•linux-azure-5.4

    < 5.4.0-1152.159~18.04.1

  • ubuntu•linux-azure-5.8

    all

  • ubuntu•linux-azure-6.11

    < 6.11.0-1013.13~24.04.1

  • ubuntu•linux-azure-6.2

    all

  • ubuntu•linux-azure-6.5

    all

  • ubuntu•linux-azure-6.8

    < 6.8.0-1027.32~22.04.1

  • ubuntu•linux-azure-edge

    all

  • ubuntu•linux-azure-fde

    all | < 5.15.0-1087.96.1

  • ubuntu•linux-azure-fde-5.19

    all

  • ubuntu•linux-azure-fde-6.2

    all

  • ubuntu•linux-azure-fips

    all | < 5.4.0-1153.160+fips1 | < 5.15.0-1087.96+fips1

  • ubuntu•linux-azure-nvidia

    < 6.8.0-1014.15

  • ubuntu•linux-bluefield

    all | < 5.4.0-1106.113 | < 5.15.0-1064.66

  • ubuntu•linux-fips

    all | < 5.4.0-1121.131 | < 5.15.0-138.148+fips1 | < 6.8.0-78.78+fips1

  • ubuntu•linux-gcp

    all | all | < 5.4.0-1150.159 | < 5.15.0-1081.90 | < 6.8.0-1028.30

  • ubuntu•linux-gcp-4.15

    all

  • ubuntu•linux-gcp-5.11

    all

  • ubuntu•linux-gcp-5.13

    all

  • ubuntu•linux-gcp-5.15

    < 5.15.0-1081.90~20.04.1

  • ubuntu•linux-gcp-5.19

    all

  • ubuntu•linux-gcp-5.3

    all

  • ubuntu•linux-gcp-5.4

    < 5.4.0-1150.159~18.04.1

  • ubuntu•linux-gcp-5.8

    all

  • ubuntu•linux-gcp-6.11

    < 6.11.0-1013.13~24.04.1

  • ubuntu•linux-gcp-6.2

    all

Showing first 50 affected entries in server-rendered view.

References (42)