CVE-2026-19028
mediumpriority · track · 0EPSS 0.002 · 9 %ileEUEPSS · scored 2026-10-27
H5Z__filter_fletcher32 in H5Zfletcher32.c in HDF5 prior to 2.3.0 computes the data length to checksum by subtracting the 4-byte trailing checksum size from the input buffer size without checking that the buffer is at least 4 bytes, allowing a size_t underflow. This allows attackers to cause a denial of service (massively out-of-bounds read and application crash in H5_checksum_fletcher32) via a crafted HDF5 file with a Fletcher32-filtered chunk smaller than 4 bytes, triggered via H5Dread, e.g. by the h5ls or h5dump tools.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (1)
Products and version ranges known to be affected.
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (9)
External citations — patches, advisories, analysis.
- https://github.com/HDFGroup/hdf5/issues/6488cnnvd
- https://github.com/HDFGroup/hdf5/issues/6490cnnvd
- https://github.com/HDFGroup/hdf5/pull/6497cnnvd
- https://github.com/HDFGroup/hdf5/issues/6488enisa_euvd
- https://github.com/HDFGroup/hdf5/issues/6490enisa_euvd
- https://github.com/HDFGroup/hdf5/pull/6497enisa_euvd
- https://github.com/HDFGroup/hdf5/issues/6488nvd
- https://github.com/HDFGroup/hdf5/issues/6490nvd
Attackers weaponise vulnerabilities like this against internet-exposed services. See what is exposed on your perimeter with a free passive scan.
Free scan