CVE-2026-120499
What it is
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.
At a glance
- Exploitability
- Can be exploited locally on the machine without logging in, but needs a user to act. High risk of data exposure, data tampering, service disruption.
- Exploit odds
- 0.4% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- ReservedThe CVE id was reserved by its CNA
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.4% in the next 30 days (EPSS).
- Severity: 8.5 HIGH (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.4% · EPSS, next 30 days
- Weakness
- CWE-95
- Record status
- Received
Attack profile CVSS 4.0 · 8.5
- Attack vector
- Local
- Complexity
- Low
- Attack requirements
- None
- Privileges needed
- None
- User interaction
- Passive
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Raw vector
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
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-120499.md and follow it. Check whether this project is affected by CVE-2026-120499. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://github.com/h5io/h5io/commit/afff1d61b31790f8c27e6c577bb7703eb1883ddd
- https://github.com/h5io/h5io/releases/tag/h5io-0.2.6
- https://github.com/h5io/h5io/security/advisories/GHSA-vwvw-f6v4-w737
- https://github.com/h5io/h5io/security/advisories/GHSA-vwvw-f6v4-w737
References
- https://github.com/h5io/h5io/blob/h5io-0.2.5/h5io/_h5io.py#L601-L604
- https://github.com/h5io/h5io/commit/afff1d61b31790f8c27e6c577bb7703eb1883ddd
- https://github.com/h5io/h5io/releases/tag/h5io-0.2.6
- https://github.com/h5io/h5io/security/advisories/GHSA-vwvw-f6v4-w737
- https://www.vulncheck.com/advisories/h5io-before-0.2.6-arbitrary-code-execution-via-read-hdf5
- https://github.com/h5io/h5io/security/advisories/GHSA-vwvw-f6v4-w737