CVE-2026-120756Low· 1.9▾ SunlitHDF5 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 rem…
▾ Sunlit zone — Low / medium · no exploitation signal
impact 10.5 · likelihood 0 · exploitation 0
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Stakeholder-Specific Vulnerability Categorization from CISA's ADP record at CVE.org: whether exploitation is observed, whether an attack can be automated, and how much of the system is at stake. The CVSS score shown above comes from the assigning CNA record, not NVD.
Exploit-prediction probability, daily snapshots since Nov 5.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via CVEORG
0.2%
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.
HDF5 < 2.3.0Refer to the linked advisories for vendor-supplied fixes and affected version ranges.
Connected by shared product, vendor, weakness, or advisory.
CVE-2026-120757Medium· 6.9Heap Buffer Over-read via Non-Terminated Link Data in H5L__extern_traverse
CVE-2026-19029Medium· 6.8A heap-based buffer over-read in H5Z__filter_scaleoffset() in src/H5Zscaleoffset.c in HDF5 through 2.2.0 lets an attacker cause a denial of service (application crash) with a crafted HDF5 file
CVE-2026-19027Medium· 6.9The H5Z__nbit_decompress_one_byte, H5Z__nbit_decompress_one_nooptype, and H5Z__nbit_decompress_one_atomic functions in H5Znbit.c in HDF5 prior to 2.3.0 advance a read index into the compressed chunk buffer without bounding it against the…
CVE-2026-19028Medium· 6.8H5Z__filter_fletcher32 in H5Zfletcher32.c in HDF5 prior to 2.3.0 computes the data length to checksum by subtracting the 4-byte trailing checksum size from the input buffer size without checking that the buffer is at least 4 bytes, allow…
CVE-2026-120758Medium· 5.4NULL Pointer Dereference in H5HL_unprotect via Corrupted File
CVE-2026-120689Medium· 4.3Uncontrolled Recursion in HDF5 H5B__iterate_helper() via Crafted File