CVE-2025-2309: HDF5 Type Conversion Logic H5T__bit_copy heap-based overflow
CSIRTS triage
- What
- Heap-based buffer overflow in HDF5 type conversion logic H5T__bit_copy function.
- Who is affected
- Applications and systems using HDF5 library for scientific data handling.
- Urgency
- Medium severity (CVSS 5.3); not exploited but memory corruption risk present.
- Action
- Apply HDF5 security patch addressing CVE-2025-2309 to affected installations.
AI-assisted analysis generated from the source advisory — verify against the original.
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Details
Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-2309
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Low exploitation riskCVE-2025-23090.33% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 25% of all EPSS-scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2025-2309 | coverage & exploitation status | NVD · CVE.org |
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