{"cve":"CVE-2026-19028","nvd":{"published":"2026-08-06T00:16:53.427","modified":"2026-10-23T21:10:00.157","status":"Awaiting Analysis","description":"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_v4":{"vector":"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","score":6.8},"cvss_v3":null,"cwes":["CWE-125","CWE-190","CWE-1284"],"references":["https://github.com/HDFGroup/hdf5/issues/6488","https://github.com/HDFGroup/hdf5/issues/6490","https://github.com/HDFGroup/hdf5/pull/6497","https://github.com/HDFGroup/hdf5/issues/6488"],"products":[],"source":"nvd","synced_at":"2026-10-24T16:53:34.184483516+00:00"},"epss":{"cve":"CVE-2026-19028","score":0.00195,"percentile":0.09058,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}