High 7.8Published Apr 9, 2026

CVE-2026-34734HDF5: H5T__conv_struct Use After Free

Updated under an hour ago (Oct 26, 2026, 4:50 PM ET)

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Every CVE for HDFGroup hdf5

Exploited in the last 30 days

HDF5 is software for managing data. In 1.14.1-2 and earlier, a heap-use-after-free was found in the h5dump helper utility. An attacker who can supply a malicious h5 file can trigger a heap use-after-free. The freed object is referenced in a memmove call from H5T__conv_struct. The original object was allocated by H5D__typeinfo_init_phase3 and freed by H5D__typeinfo_term.

CVSS: 7.8 HIGH (v3.1, CNA)CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Weakness (CWE): CWE-416, CWE-825
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Modified
Record last updated: Jul 14, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

HDFGroup hdf5 hdfgroup:hdf5 (from the name)	through 1.14.1-2	CNA record
Red Hat Red Hat Enterprise Linux AI (RHEL AI) 3 redhat:enterprise_linux_ai	3	CISA ADP
hdfgroup hdf5 hdfgroup:hdf5	before 1.14.1-2	NVD

References

References

https://github.com/HDFGroup/hdf5/security/advisories/GHSA-w7v2-9cmr-pwwj	x-refsource-confirm, exploit, vendor-advisory
https://access.redhat.com/security/cve/CVE-2026-34734
https://bugzilla.redhat.com/show_bug.cgi?id=2457034
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-34734.json

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.