CVE-2026-19028: medium-severity vulnerability in The HDF Group HDF5
HDF5 integer underflow in Fletcher32 filter leads to massive out-of-bounds read
Published · Updated
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13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 6.8epss 0.2%
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:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Affected products
The HDF Group · HDF5Related CVEs — The HDF Group HDF5
In the same product, most dangerous first.
CVE-2026-92627MEDIUMHeap Use-After-Free in H5T__conv_f_fEPSS 0.2%CVE-2026-19027MEDIUMHDF5 out-of-bounds heap read in N-Bit filter decompressionEPSS 0.2%CVE-2026-19026MEDIUMNbit filter NULL/short parameter-array dereferenceEPSS 0.2%CVE-2026-19024HIGHHDF5 H5Pget_fill_value NULL Pointer Dereference via Malformed Fill Value MessageEPSS 0.2%CVE-2026-19025MEDIUMHDF5 divide-by-zero (SIGFPE) via mismatched chunk-layout dimensionality and dataspace rank on dataset openEPSS 0.2%CVE-2026-19023MEDIUMHDF5 h5dump Untrusted Pointer Dereference in Binary Output of Variable-Length String DatasetsEPSS 0.2%