PatchSiren cyber security CVE debrief

CVE-2026-46128 Linux CVE debrief

A vulnerability in the Linux kernel's IPMI subsystem has been resolved. The issue involved insufficient validation of event message buffer response data sizes. Some Baseboard Management Controllers (BMCs) were returning empty messages instead of proper error codes when fetching events, which could lead to processing of malformed data. The fix adds immediate size checking upon response receipt, rather than deferring validation to later processing stages. This is a defensive hardening measure triggered by behavior observed in newer BMC hardware.

Vendor: Linux
Product: Unknown
CVSS: MEDIUM 5.5
CISA KEV: Not listed in stored evidence
Original CVE published: 2026-05-28
Original CVE updated: 2026-06-24
Advisory published: 2026-05-28
Advisory updated: 2026-06-24

Who should care

System administrators managing servers with IPMI/BMC functionality, Linux distribution maintainers, and organizations running Linux on hardware with Baseboard Management Controllers

Technical summary

The Linux kernel IPMI driver did not validate event message buffer response data sizes immediately upon receipt. Some BMC implementations return empty messages rather than error codes when event fetching fails. The vulnerability is resolved by adding early size validation to prevent processing of malformed responses. Patches are available for multiple stable kernel branches.

Defensive priority

medium

Recommended defensive actions

Apply the relevant stable kernel patch for your kernel version
Monitor kernel stable mailing lists for backport availability to your specific kernel branch
Review IPMI/BMC firmware versions and consider updates if available from hardware vendors
Verify IPMI event logging functionality after kernel update to ensure proper operation

Evidence notes

The vulnerability description indicates this is a resolved kernel issue with patches available. The fix involves adding early validation of IPMI event message buffer responses to handle BMCs that return empty messages. Multiple stable kernel branch commits are referenced, suggesting backports to supported kernel versions.

Sources and references

Verified primary and authoritative sources

CVE-2026-46128 CVE Program record
Publisher, destination, and source semantics verified

URL: https://www.cve.org/CVERecord?id=CVE-2026-46128

CVE Program - Official CVE Program record with source-provided CVE metadata.
CVE-2026-46128 NVD vulnerability detail
Publisher, destination, and source semantics verified

URL: https://nvd.nist.gov/vuln/detail/CVE-2026-46128

NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

Source reference
Unverified legacy reference

URL: https://git.kernel.org/stable/c/2418e4b21fb1355504d095da5d5f0a210564a43d

416baaa9-dc9f-4396-8d5f-8c081fb06d67
Source reference
Unverified legacy reference

URL: https://git.kernel.org/stable/c/24269264c3d59a49eb09b10af2c75b14f2931482

416baaa9-dc9f-4396-8d5f-8c081fb06d67
Source reference
Unverified legacy reference

URL: https://git.kernel.org/stable/c/36920f30e78e69df01f9691c470b6f3ba8aebf98

416baaa9-dc9f-4396-8d5f-8c081fb06d67
Source reference
Unverified legacy reference

URL: https://git.kernel.org/stable/c/42432b579a594b66ac32e5e7b7c26e6bc578ec89

416baaa9-dc9f-4396-8d5f-8c081fb06d67
Source reference
Unverified legacy reference

URL: https://git.kernel.org/stable/c/7f7ada72c07a83b46045ddfeee526bd9e2e3c8f0

416baaa9-dc9f-4396-8d5f-8c081fb06d67

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.