CVE-2026-120499
h5io before 0.2.6 Arbitrary Code Execution via read_hdf5
h5io before 0.2.6 contains a code injection vulnerability in read_hdf5() that allows attackers to execute arbitrary code by supplying a crafted HDF5 file. Attackers can store Python code in a node titled timezone, which _triage_read() passes to eval() with builtins reachable, name an arbitrary module in class or custom-object nodes that _import_class() imports, or place pickled objects in pd_dataframe or pd_series nodes that pandas deserializes on read.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Passive
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
8.5
h5io before 0.2.6 Arbitrary Code Execution via read_hdf5
h5io before 0.2.6 contains a code injection vulnerability in read_hdf5() that allows attackers to execute arbitrary code by supplying a crafted HDF5 file. Attackers can store Python code in a node titled timezone, which _triage_read() passes to eval() with builtins reachable, name an arbitrary module in class or custom-object nodes that _import_class() imports, or place pickled objects in pd_dataframe or pd_series nodes that pandas deserializes on read.
- Record
CVE-2026-120499- CVSS 4.0
- 8.5 High
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-95, CWE-502
- Updated
- 2026-11-05
EUVDEUVD-2026-117602
8.5
h5io before 0.2.6 contains a code injection vulnerability in read_hdf5() that allows attackers to execute arbitrary code by supplying a crafted HDF5 file. Attackers can store Python code in a node titled timezone, which _triage_read() passes to eval() with builtins reachable, name an arbitrary module in class or custom-object nodes that _import_class() imports, or place pickled objects in pd_dataframe or pd_series nodes that pandas deserializes on read.
- Record
EUVD-2026-117602- CVSS 4.0
- 8.5 High
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - Updated
- 2026-11-05
NVD
8.5
h5io before 0.2.6 contains a code injection vulnerability in read_hdf5() that allows attackers to execute arbitrary code by supplying a crafted HDF5 file. Attackers can store Python code in a node titled timezone, which _triage_read() passes to eval() with builtins reachable, name an arbitrary module in class or custom-object nodes that _import_class() imports, or place pickled objects in pd_dataframe or pd_series nodes that pandas deserializes on read.
- Record
CVE-2026-120499- CVSS 4.0
- 8.5 High
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/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:X - CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-95, CWE-502
- Updated
- 2026-11-05
OSV
8.5
h5io before 0.2.6 Arbitrary Code Execution via read_hdf5
h5io before 0.2.6 contains a code injection vulnerability in read_hdf5() that allows attackers to execute arbitrary code by supplying a crafted HDF5 file. Attackers can store Python code in a node titled timezone, which _triage_read() passes to eval() with builtins reachable, name an arbitrary module in class or custom-object nodes that _import_class() imports, or place pickled objects in pd_dataframe or pd_series nodes that pandas deserializes on read.
- Record
CVE-2026-120499- CVSS 4.0
- 8.5 High
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - Weakness
- CWE-502, CWE-95
- Updated
- 2026-11-07
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| references | OSV | |
| aliases, references | NVD, OSV | |
| references | CVE List, EUVD, NVD | |
| aliases, published | EUVD | |
| first indexed | CVE List |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-120499 is a high vulnerability (CVSS 8.5) in H5io, published November 5, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.42%, the 36th percentile. No source names a fixed version.
References
github.com/h5io/h5io/security/advisories/GHSA-vwvw-f6v4-w737
github.com/h5io/h5io/commit/afff1d61b31790f8c27e6c577bb7703eb1883ddd
github.com/h5io/h5io/releases/tag/h5io-0.2.6
github.com/h5io/h5io/blob/h5io-0.2.5/h5io/_h5io.py
vulncheck.com/advisories/h5io-before-0.2.6-arbitrary-code-execution-via-read-hdf5
github.com/CVEProject/cvelistV5/tree/main/cves/2026/120xxx/CVE-2026-120499.json
nvd.nist.gov/vuln/detail/CVE-2026-120499
github.com/h5io/h5io