CVE-2026-120756 (GCVE-0-2026-120756)
Vulnerability from cvelistv5 – Published: 2026-11-03 15:32 – Updated: 2026-11-03 17:55
VLAI
EPSS
VEX
Title
Heap Buffer Over-read via Malformed Message Size in HDF5's H5O__chunk_deserialize
Summary
HDF5 through 2.2.0 contains a heap buffer over-read vulnerability in H5O__chunk_deserialize() in src/H5Ocache.c. When decoding object header messages, the declared message size is checked against the end of the chunk image before the remainder of the message header (flags, and for version 2 object headers, the optional creation index) has been decoded. Because the message body begins after these fields, a message can start up to four bytes further into the chunk than the size check accounts for. A crafted HDF5 file can declare a message size that passes the check but extends past the end of the chunk image, causing the message’s decode callback, for example H5O__mtime_new_decode() in src/H5Omtime.c, to read beyond the heap allocation. The flaw is reachable during H5Fopen() on a crafted file. An attacker who can get a user or application to open a malicious file can cause a denial of service or limited disclosure of process memory.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-11-03 17:55 UTC
CWE
- CWE-125 - Out-of-bounds read
Assigner
References
2 references
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| The HDF Group | HDF5 |
Affected:
< 2.3.0
|
guessed |
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