CVE-2026-19029 and is rated Medium severity with a CVSS score of 6.8. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.
What to do next
Remediation and response
Microsoft Security Response Center guidance
Vendor revision: Oct 8, 2026
Release Notes
CISA KEVNot listedBased on the latest collected catalog
EPSS0.1%Estimated 30-day exploitation probability
Ransomware useNot markedCISA KEV ransomware field
Threat actors0Source-linked actor relationships
Overview
What is CVE-2026-19029?
A heap-based buffer over-read in H5Z__filter_scaleoffset() in src/H5Zscaleoffset.c in HDF5 through 2.2.0 lets an attacker cause a denial of service (application crash) with a crafted HDF5 file. When the stored minimum bits equal the full precision of the datatype, the decoder copies d_nelmts * size bytes from the compressed chunk without checking that the chunk holds that many bytes.
Both values come from attacker-controlled scale-offset filter parameters in the dataset's filter pipeline message.