Microsoft security update for CVE-2025-21993
🔗 CVE IDs covered (1)
📋 Microsoft's advisory
EchelonGraph does not copy Microsoft's advisory page: its FAQ and remediation text are not shown here. Read the advisory on https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21993. This page also shows what EchelonGraph holds for CVE-2025-21993, with the description from its CVE record, which the CVE Numbering Authority that assigned the CVE wrote: for a CVE Microsoft assigned, often in the words of Microsoft's own advisory.
🎯 Affected products5
- azl3 kernel 6.6.82.1-1 on Azure Linux 3.0
- azl3 kernel 6.6.85.1-2 on Azure Linux 3.0
- cbl2 kernel 5.15.180.1-1 on CBL Mariner 2.0
- cbl2 kernel 5.15.182.1-1 on CBL Mariner 2.0
- cbl2 kernel 5.15.182.1-1 on CBL-Mariner 2.0
✅ Updates Microsoft lists: 3 updates
3 rows: one per KB article or update, update type and fixed build. Their details are on Microsoft's advisory.
| KB article | Update | Fixed build |
|---|---|---|
| — | Security Update | — |
| — | Security Update | 5.15.180.1-1 |
| — | Security Update | 6.6.85.1-2 |
🧭 EchelonGraph on CVE-2025-21993
- EchelonGraph score
- 7.1 HIGH
- CISA KEV
- Not listed
- Fix status
- A fix is available — apply it.
Description from the CVE record (CVE.org), as published by its numbering authority
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.
Published by kernel.org, the CVE Numbering Authority that assigned CVE-2025-21993, in its CVE record at CVE.org; reused under the CVE Program's Terms of Use (its licence and MITRE's copyright notice are in our Terms of Service).