CVE-2025-6516: HDF5 H5Fint.c H5F_addr_decode_len heap-based overflow
CSIRTS triage
- What
- A heap-based buffer overflow exists in the H5F_addr_decode_len function of HDF5 library's H5Fint.c.
- Who is affected
- Applications using HDF5 library in affected versions.
- Urgency
- Medium severity (CVSS 5.3) but not exploited; standard patching applies.
- Action
- Update HDF5 library to a patched version when available.
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Details
Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-6516
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-2025-65160.31% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 23% of all EPSS-scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2025-6516 | coverage & exploitation status | NVD · CVE.org |
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