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.
Weakness
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory “belongs” to the code that operates on the new pointer.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Hdf5 | Hdfgroup | * | 1.14.1-2 (excluding) |
| Hdf5 | Ubuntu | esm-apps/xenial | * |
| Hdf5 | Ubuntu | questing | * |
Potential Mitigations
References
- https://github.com/HDFGroup/hdf5/security/advisories/GHSA-w7v2-9cmr-pwwj
- https://access.redhat.com/security/cve/CVE-2026-34734
- https://bugzilla.redhat.com/show_bug.cgi?id=2457034
- https://github.com/HDFGroup/hdf5/security/advisories/GHSA-w7v2-9cmr-pwwj
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-34734.json