CVE-2024-32616

What it actually does

Heap-based buffer over-read in H5O__dtype_encode_helper allows reading beyond allocated memory during datatype encoding of HDF5 files, potentially disclosing adjacent heap contents or causing crashes.

Why it matters to the business

Applications processing untrusted HDF5 files risk memory disclosure or denial of service, disrupting scientific data workflows and potentially exposing sensitive information in shared environments.

How an attack unfolds

An attacker crafts a malformed HDF5 file that triggers the buffer over-read path in H5O__dtype_encode_helper when the library parses the datatype object; the flaw can be triggered locally without authentication when an affected application opens the file.

How to fix it

Upgrade hdfgroup/hdf5 to the commit 88429b015e29c59de604b0f552001fb7cb7ed5d0 or later release that resolves the over-read; rebuild and redeploy dependent applications.

How to confirm the fix worked

Confirm library version is newer than 1.14.3 and contains commit 88429b015e29c59de604b0f552001fb7cb7ed5d0; test with known-malformed dtype files to verify no over-read occurs.

Typical attack path

1. Attacker creates malicious HDF5 file exploiting the dtype encoding path
2. Victim application or tool opens the file using vulnerable HDF5 library <= 1.14.3
3. H5O__dtype_encode_helper performs the heap over-read during parsing
4. Attacker observes leaked memory contents or triggers application crash

How to detect it

Review application logs for crashes or errors during HDF5 file parsing; inspect process memory dumps or core files around H5Odtype.c for evidence of over-read attempts; correlate file opens with subsequent anomalous behavior.

What your security team should do

• Immediately update all HDF5 installations to the fixed commit
• Scan for and replace any embedded or vendored copies of vulnerable HDF5
• Restrict processing of untrusted HDF5 files until patches are applied
• Monitor EPSS and KEV status for changes in exploit availability