CVE-2025-6516: HDF5 H5Fint.c H5F_addr_decode_len heap-based overflow
Vulnerability summary
CVE-2025-6516 is a high (CVSS 7.8) vulnerability in hdfgroup hdf5. EPSS estimates a 0.39% chance of exploitation in the next 30 days, higher than 32.6% of scored vulnerabilities. 2 public exploits are recorded.
Not severe (CVSS 4.8, local access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 1Timeline
- 23-06-2025PublishedVulnerability first disclosed.
- 23-06-2025Last modifiedVulnerability information updated.
Description
A vulnerability has been found in HDF5 up to 1.14.6 and classified as critical. This vulnerability affects the function H5F_addr_decode_len of the file /hdf5/src/H5Fint.c. The manipulation leads to heap-based buffer overflow. An attack has to be approached locally. The exploit has been disclosed to the public and may be used.
CVSS metrics
10 scores · 4 sources · 4 versions- OSV · UbuntuEcosystem advisory · calculated4.8MediumCVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P
- NVDNIST1.9LowCVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:XDiffers
- CVE.orgCNA5.3MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L/E:P/RL:X/RC:RDiffers
- OSV · UbuntuEcosystem advisory · calculated7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- NVDNIST4.3MediumAV:L/AC:L/Au:S/C:P/I:P/A:P
EPSS trend
Probability
0.39%
Chance of exploitation in the next 30 days
Percentile
33%
Versus all other CVEs
30-day change
Increase +0.01 pp
From 0.38% on 04-10-2026
Known exploited
Compare KEV catalogsNot in the CISA KEV catalog.
Not in the ENISA CNW catalog.
Not in the CIRCL catalog.
Public exploits
2 foundFiles
Maturity: poc
Hdf5
Maturity: poc
Weaknesses
CWE · root cause- CWE-119Improper Restriction of Operations within the Bounds of a Memory BufferThe product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary.
- CWE-122Heap-based Buffer OverflowThe product writes past the end of a buffer that was allocated on the heap.
- CWE-787Out-of-bounds WriteThe product writes data past the end, or before the beginning, of the intended buffer.
Affected systems
Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.
Debian1 product
- hdf5All versions (No fix recorded) | < 2.1.0+repack-1
Hdfgroup1 product
- hdf5≤ 1.14.6
Ubuntu1 product
- hdf5All versions (No fix recorded)
3 vendors · 3 products