CVE-2026-34734
HDF5: H5T__conv_struct Use After Free
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.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
HDF5: H5T__conv_struct Use After Free
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.
- Record
CVE-2026-34734- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-416, CWE-825
- Updated
- 2026-11-02
EUVDEUVD-2026-21020
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.
- Record
EUVD-2026-21020- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
NVD
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.
- Record
CVE-2026-34734- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-416, CWE-825
- Updated
- 2026-11-02
OSV
HDF5: H5T__conv_struct Use After Free
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.
- Record
CVE-2026-34734- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-416
- Updated
- 2026-11-02
OSVDEBIAN-CVE-2026-34734
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.
- Record
DEBIAN-CVE-2026-34734- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVJLSEC-2026-354
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.
- Record
JLSEC-2026-354- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVRHSA-2026:61630
Red Hat Security Advisory: Red Hat Hardened Images RPMs Security Update
- Record
RHSA-2026:61630- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVUBUNTU-CVE-2026-34734
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.
- Record
UBUNTU-CVE-2026-34734- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
hdf5Debian:12 |
All versions, plus listed versions 1.10.10+repack-11.10.10+repack-21.10.10+repack-31.10.10+repack-3.11.10.10+repack-3.2 Show 45 moreShow less1.10.10+repack-3.2+ports1.10.10+repack-3.31.10.10+repack-41.10.10+repack-51.10.8+repack1-11.12.0+repack-1~exp11.12.0+repack-1~exp21.12.2+repack-1~exp11.14.3+repack-1~exp11.14.3+repack1-1~exp21.14.3+repack1-1~exp31.14.4.3+repack-1~exp11.14.4.3+repack-1~exp21.14.4.3+repack-1~exp31.14.5+repack-11.14.5+repack-1~exp11.14.5+repack-1~exp21.14.5+repack-1~exp31.14.5+repack-1~exp41.14.5+repack-1~exp51.14.5+repack-1~exp61.14.5+repack-21.14.5+repack-31.14.5+repack-3.11.14.5+repack-3~exp11.14.5+repack-3~exp21.14.5+repack-3~exp31.14.5+repack-3~exp41.14.5+repack-41.14.5+repack-4~exp11.14.5+repack-4~exp21.14.5+repack-5~exp21.14.5+repack-5~exp31.14.6+repack-11.14.6+repack-1~exp11.14.6+repack-1~exp101.14.6+repack-1~exp111.14.6+repack-1~exp121.14.6+repack-1~exp131.14.6+repack-1~exp141.14.6+repack-1~exp151.14.6+repack-1~exp161.14.6+repack-1~exp171.14.6+repack-1~exp181.14.6+repack-1~exp19 |
None known |
hdf5Debian:13 |
All versions, plus listed versions 1.14.5+repack-31.14.5+repack-3.11.14.5+repack-41.14.5+repack-4~exp11.14.5+repack-4~exp2 Show 41 moreShow less1.14.5+repack-5~exp21.14.5+repack-5~exp31.14.6+repack-11.14.6+repack-1~exp11.14.6+repack-1~exp101.14.6+repack-1~exp111.14.6+repack-1~exp121.14.6+repack-1~exp131.14.6+repack-1~exp141.14.6+repack-1~exp151.14.6+repack-1~exp161.14.6+repack-1~exp171.14.6+repack-1~exp181.14.6+repack-1~exp191.14.6+repack-1~exp21.14.6+repack-1~exp201.14.6+repack-1~exp211.14.6+repack-1~exp31.14.6+repack-1~exp41.14.6+repack-1~exp51.14.6+repack-1~exp61.14.6+repack-1~exp71.14.6+repack-1~exp81.14.6+repack-1~exp91.14.6+repack-21.14.6+repack-3~exp12.1.0+repack-12.1.0+repack-1~exp102.1.0+repack-1~exp112.1.0+repack-1~exp32.1.0+repack-1~exp42.1.0+repack-1~exp52.1.0+repack-1~exp62.1.0+repack-1~exp72.1.0+repack-1~exp82.1.0+repack-1~exp92.2.0+repack-12.2.0+repack-22.2.0+repack-32.2.0+repack-42.2.0+repack-5 |
None known |
hdf5Debian:14 |
All versions, plus listed versions 1.14.5+repack-31.14.5+repack-3.11.14.5+repack-41.14.5+repack-4~exp11.14.5+repack-4~exp2 Show 41 moreShow less1.14.5+repack-5~exp21.14.5+repack-5~exp31.14.6+repack-11.14.6+repack-1~exp11.14.6+repack-1~exp101.14.6+repack-1~exp111.14.6+repack-1~exp121.14.6+repack-1~exp131.14.6+repack-1~exp141.14.6+repack-1~exp151.14.6+repack-1~exp161.14.6+repack-1~exp171.14.6+repack-1~exp181.14.6+repack-1~exp191.14.6+repack-1~exp21.14.6+repack-1~exp201.14.6+repack-1~exp211.14.6+repack-1~exp31.14.6+repack-1~exp41.14.6+repack-1~exp51.14.6+repack-1~exp61.14.6+repack-1~exp71.14.6+repack-1~exp81.14.6+repack-1~exp91.14.6+repack-21.14.6+repack-3~exp12.1.0+repack-12.1.0+repack-1~exp102.1.0+repack-1~exp112.1.0+repack-1~exp32.1.0+repack-1~exp42.1.0+repack-1~exp52.1.0+repack-1~exp62.1.0+repack-1~exp72.1.0+repack-1~exp82.1.0+repack-1~exp92.2.0+repack-12.2.0+repack-22.2.0+repack-32.2.0+repack-42.2.0+repack-5 |
None known |
HDF5_jllJulia |
before 1.14.2+0 | 1.14.2+0 |
hdf5Red Hat:hummingbird:1 From an advisory covering 6 CVEs |
before 0:2.2.0-0.1.1.hum1 | 0:2.2.0-0.1.1.hum1 |
hdf5-develRed Hat:hummingbird:1 From an advisory covering 6 CVEs |
before 0:2.2.0-0.1.1.hum1 | 0:2.2.0-0.1.1.hum1 |
hdf5-mpichRed Hat:hummingbird:1 From an advisory covering 6 CVEs |
before 0:2.2.0-0.1.1.hum1 | 0:2.2.0-0.1.1.hum1 |
hdf5-mpich-develRed Hat:hummingbird:1 From an advisory covering 6 CVEs |
before 0:2.2.0-0.1.1.hum1 | 0:2.2.0-0.1.1.hum1 |
hdf5-mpich-staticRed Hat:hummingbird:1 From an advisory covering 6 CVEs |
before 0:2.2.0-0.1.1.hum1 | 0:2.2.0-0.1.1.hum1 |
hdf5-openmpiRed Hat:hummingbird:1 From an advisory covering 6 CVEs |
before 0:2.2.0-0.1.1.hum1 | 0:2.2.0-0.1.1.hum1 |
Show 13 moreShow less
| Package | Affected | Fixed |
|---|---|---|
hdf5-openmpi-develRed Hat:hummingbird:1 From an advisory covering 6 CVEs |
before 0:2.2.0-0.1.1.hum1 | 0:2.2.0-0.1.1.hum1 |
hdf5-openmpi-staticRed Hat:hummingbird:1 From an advisory covering 6 CVEs |
before 0:2.2.0-0.1.1.hum1 | 0:2.2.0-0.1.1.hum1 |
hdf5-staticRed Hat:hummingbird:1 From an advisory covering 6 CVEs |
before 0:2.2.0-0.1.1.hum1 | 0:2.2.0-0.1.1.hum1 |
java-hdf5Red Hat:hummingbird:1 From an advisory covering 6 CVEs |
before 0:2.2.0-0.1.1.hum1 | 0:2.2.0-0.1.1.hum1 |
hdf5Ubuntu:Pro:14.04:LTS |
All versions, plus listed versions 1.8.11-3ubuntu11.8.11-5ubuntu11.8.11-5ubuntu21.8.11-5ubuntu61.8.11-5ubuntu71.8.11-5ubuntu7.11.8.11-5ubuntu7.1+esm11.8.11-5ubuntu7.1+esm2 |
None known |
hdf5Ubuntu:Pro:16.04:LTS |
All versions, plus listed versions 1.8.15-patch1+docs-41.8.15-patch1+docs-51.8.16+docs-11.8.16+docs-21.8.16+docs-3 Show 6 moreShow less1.8.16+docs-3ubuntu11.8.16+docs-41.8.16+docs-4ubuntu11.8.16+docs-4ubuntu1.11.8.16+docs-4ubuntu1.1+esm11.8.16+docs-4ubuntu1.1+esm2 |
None known |
hdf5Ubuntu:Pro:18.04:LTS |
All versions, plus listed versions 1.10.0-patch1+docs-41.10.0-patch1+docs-4ubuntu0.1~esm11.10.0-patch1+docs-4ubuntu0.1~esm2 |
None known |
hdf5Ubuntu:Pro:20.04:LTS |
All versions, plus listed versions 1.10.4+repack-101.10.4+repack-111.10.4+repack-11ubuntu11.10.4+repack-11ubuntu1+esm1 |
None known |
hdf5Ubuntu:22.04:LTS |
All versions, plus listed versions 1.10.6+repack-51.10.7+repack-4ubuntu11.10.7+repack-4ubuntu2 |
None known |
hdf5Ubuntu:24.04:LTS |
All versions, plus listed versions 1.10.8+repack1-1ubuntu11.10.10+repack-3ubuntu11.10.10+repack-3.1ubuntu31.10.10+repack-3.1ubuntu4 |
None known |
hdf5Ubuntu:25.10 |
All versions, plus listed versions 1.14.5+repack-31.14.5+repack-3build1 |
None known |
hdf5Ubuntu:26.10 |
All versions, plus listed versions 1.14.6+repack-22.2.0+repack-42.2.0+repack-5 |
None known |
hdf5Ubuntu:26.04:LTS |
All versions, plus listed versions 1.14.5+repack-3build11.14.5+repack-41.14.6+repack-2 |
None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected, facts | ||
| first indexed | CVE List, EUVD, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-34734 is a high vulnerability (CVSS 7.8) in Hdfgroup Hdf5, published April 9, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.20%, the 9th percentile. Fixed in HDF5_jll 1.14.2+0.
References
github.com/HDFGroup/hdf5/security/advisories/GHSA-w7v2-9cmr-pwwj
access.redhat.com/security/cve/CVE-2026-34734
bugzilla.redhat.com/show_bug.cgi?id=2457034
security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-34734.json
nvd.nist.gov/vuln/detail/CVE-2026-34734
Show 32 moreShow less
security-tracker.debian.org/tracker/CVE-2026-34734
images.redhat.com
cve.org/CVERecord?id=CVE-2026-17572
pulsesecurity.co.nz/advisories/hdf5-memory-corruption
ubuntu.com/security/CVE-2026-34734
Left out here: 27 versions. The JSON record has them.