High severity · published Oct 6, 2026
CVE-2026-106440
Hydra: Optuna custom_search_space can resolve and execute untrusted callables via get_method
7.8
CVSS
0.3%
EPSS
No
On KEV
Description
Hydra is a framework for elegantly configuring complex applications. From 1.2.0 until 1.3.0 and 1.4.0.dev10, the hydra-optuna-sweeper package accepts a configuration-controlled dotted path in hydra.sweeper.custom_search_space, resolves it with hydra.utils.get_method(), and later invokes the returned callable in the Hydra controller process. Because get_method() is a trusted-input lookup helper and does not apply the execution policy used by instantiate(), an attacker who controls Optuna sweep configuration or command-line overrides can select importable Python code for execution with the application's privileges, including bypassing a trusted execution whitelist on affected Hydra 1.4 development releases. This issue is fixed in versions 1.3.0 and 1.4.0.dev10.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Attack vector
Local
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 19% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
HY
hydra · hydra-ecosystem
>= 1.2.0, < 1.3.0; >= 1.4.0.dev4, < 1.4.0.dev10 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-106440
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-106440
x_refsource_CONFIRM
https://github.com/hydra-ecosystem/hydra/security/advisories/GHSA-5jjj-9xc3-rm56
x_refsource_MISC
https://github.com/hydra-ecosystem/hydra/commit/0dd18084589a3d3e577d1f1a8a48fb485c94a5e6
x_refsource_MISC
https://github.com/hydra-ecosystem/hydra/commit/4720dfca2bde27fa140ec287a05709668fbdf168
x_refsource_MISC
https://github.com/hydra-ecosystem/hydra/releases/tag/v1.3.7
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